Document Imaging Definitions/Glossary/Terms

This page contains definitions to a host of commonly used document imaging, document management and workflow terms.

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Accelerator is a device or software designed to speed up operations, such as refreshing a screen image. Many PC SVGA graphics boards come furnished with accelerator chips. There are also auxiliary boards (commonly called pass-through boards) that will boost the speed of regular VGA boards.

Access Time refers to the time required for a data storage device to locate and retrieve data.

Additive Colors - Red, Green, and Blue are referred to as additive colors. Red+Green+Blue=White.
Algorithm The specific process in a computer program used to solve a particular problem.

Aliasing is an effect caused by sampling an image (or signal) at too low a rate. It makes rapid change (high texture) areas of an image appear as a slow change in the sample image. Once aliasing occurs, there is no way to accurately reproduce the original image from the sampled image.

Analog transmitted data can be represented electronically by a continuous wave form signal. Examples of analog items are traditional photographed images and phonograph albums.

Analog to Digital Converter (A/D Converter) is a device that converts analog information (a photograph or video frame) into a series of numbers that a computer can store and manipulate.

Annotation and Markup Features allow you to add comments to an electronic document in much the same way that you would use highlighters or Post-it notes to draw attention to specific areas of a printed document.
Aperture Card is a standard Hollerith encoded IBM-style punch card that acts as a transport for a 35mm transparency. Typically, aperture cards are used to store blueprints and engineering drawings.

Anti-aliasing is the process of reducing stair-stepping by smoothing edges where individual pixels are visible.
Aperture Card Scanner is a type of scanner that allows aperture cards to be converted into electronic documents.
Application A computer software program designed to meet a specific need.

APRP (Adaptive Pattern Recognition Processing) is one of the most sophisticated technologies currently available in modern text retrieval software. APRP automatically indexes the binary patterns in digital information, creating a pattern-based memory that is optimized for the content of the data. It eliminates the costly labor of manually defining keywords and sorting and labeling information in database fields. APRP has a high tolerance for input data errors, eliminating the need for OCR clean up.

APS is an abbreviation for Advanced Photo System. It is a film cartridge system that magnetically records all picture data for each frame of film. This data is then used by the photo finisher to provide you with better pictures and new services that can't be found with traditional film cameras.

Archival Image is an image meant to have lasting utility. Archival images are usually kept off-line on a cheaper storage medium such as CD-ROM or magnetic tape, in a secure environment. Archival images are of a higher resolution and quality than the digital image delivered to the user on-screen. The file format most often associated with archival images is TIFF, or Tagged Image File Format, as compared to on-screen viewing file formats, which are usually JPEGs and GIFs.

Archival Scans are digital images serving as surrogates of the original. At this point in time, there is no such thing as an Archival or Preservation scan that acts as an exact replica or replacement of the original, as it is not yet possible to record every piece of information found in the original with today's scanner technology.

Archive is the long-term storage of data or images. Archiving is generally accomplished on some form of magnetic media; such as disk or tape, or optical media; such as Writable CD.

Artifacts are visual digital effects introduced into an image during scanning that do not correspond to the original image being scanned. Artifacts might include pixellation, dotted or straight lines, regularly repeated patterns, moire, etc.

Aspect Ratio refers to the ratio of horizontal to vertical dimensions of an image. (35mm slide frame is 3:2, TV 4:3, HDTV 16:9, 4X5 film 5:4)

ATM (Asynchronous Transfer Mode) is a network protocol that transfers data in cells or packets of a small fixed size. The small, fixed size of ATM allows data such as video, voice and data to be transferred over the same network.

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Background Processing is a feature that enables the computer operator to continue working while the computer executes another action, such as spooling data to a printer.
Banding is an artifact of color gradation in computer imaging, when graduated colors break into larger blocks of a single color, reducing the "smooth" look of a proper gradation.

Bandwidth defines the amount of information that can travel between two points in a specific time.

Binary is a coding or counting system with only two symbols or conditions (off/on, zero/one, mark/space, high/low). The binary system is the basis for storing data in computers.

Bit is a binary digit, a fundamental digital quantity representing either 1 or 0 (on or off).

Bitmap(BMP) is an image made up of dots, or pixels. Refers to a raster image, in which the image consists of rows or pixels rather than vector coordinates.

Brightness refers to the value of a pixel in an electronic image, representing its lightness value from black to white. Usually defined as brightness levels ranging in value from 0 (black) to 255 (white).

Buffer is temporary storage area usually held in RAM. The purpose of a buffer is to act as a temporary holding area for data that will allow the CPU to manipulate data before transferring it to a device.

Bulletin Board Service or BBS is a dial-up computer service accessible by modem, usually maintained by a manufacturer, distributor, or private company. They're used for 2-way computer-to-computer communications, to download patches and utilities, to allow users to ask questions and access information, to receive company announcements, etc.

Byte refers to an ensemble of eight bits of memory in a computer.

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Calibration is the act of adjusting the color of one device relative to another, such as a monitor to a printer, or a scanner to a film recorder. Or, it may be the process of adjusting the color of one device to some established standard.

CD is the abbreviation for compact disc, a laser-encoded plastic medium designed to store a large amount of data. A variety of CD formats are available for use by computers.

CD drive is a drive mechanism for recording or playing CDs. The most common types are CD-ROM, MO (magneto-optical), and WORM (Write Once, Read Many).

CD-ReWritable Media A product on which users can record text, images and graphics for permanent or temporary storage. Because it allows multiple recordings, users can erase and rewrite as often as needed.

CD-ROM (Compact Disc, Read-Only Memory) A non-rewritable CD used by a computer as a storage medium for data.

CCD Array Charge-Coupled Device array. Light sensitive diodes used in scanners and digital cameras that sweep across an image during capture and, when exposed to light, generate a series of digital signals that are converted into pixel values.

CCD-Charged Coupled Device A charged coupled device (CCD) converts light into proportional (analog) electrical current. The two main types of CCDs are linear arrays used in flatbed scanners, digital copiers, and graphic arts scanners, and area arrays used in camcorders, still-video cameras, digital cameras, and fast scanners.

Channel is one piece of information stored with an image. True color images, for instance, have three channels-red, green and blue.

Chroma is the color of an image element (pixel). Chroma is made up of saturation + hue values, but separate from the luminance value.

Chromatic Adaption refers to the Adjustment to overall color shifts, like those produced by filters.

Clip Art refers to graphic files that are usually distributed on CD-ROMS and can be inserted into documents, presentations, and projects.

Client-Server Based System is a system that stores electronic documents on one computer—a server, while making those documents available to other computers—clients, via a network.

CMOS is an abbreviation for Complimentary Metal Oxide Semiconductor. In this case CMOS are light sensors that capture images taken by digital cameras. Usually they are found in high-end digital cameras with megapixel sensors.

CMS (Color Matching System) (Color Management System) is a software program (or a software and hardware combination) designed to ensure color matching and calibration between video or computer monitors and any form of hard copy output.

CMY (Cyan, Magenta, Yellow) The three subtractive color primaries.

CMYK (Cyan, Magenta, Yellow, Black) One of several color encoding system used by printers for combining primary colors to produce a full-color image. In CMYK, colors are expressed by the "subtractive primaries" (cyan, magenta, yellow) and black. Black is called "K" or keyline since black, keylined text appears on this layer.

COD (Computer Originated Document) refers to any document that was originally created on a computer, like a word processing document or a spreadsheet.

Codec (Coder/decoder) Compresses information so that it can be sent across a network faster, and decompresses information received via the network.

COLD (Computer Output to Laser Disk) software allows you to transfer documents from expensive mainframe storage, onto an inexpensive, long-term optical disk storage system.

Collection refers to two or more electronic documents containing related information that have been grouped together to facilitate retrieval.

Color Correction The process of correcting or enhancing the color of an image.

Color Wheel This is an aid to be used when selecting colors for a harmonious color scheme. You can easily identify and split complementary colors.

Compact Flash A type of storage card used in digital cameras to store images captured by the camera. The Compact Flash can then be erased when the images have been transferred or are no longer needed, the card can be erased and reused. It also fits into a PCMCIA adapter eliminating the need to connect the camera to some computer systems.

Compression/Decompression is the reduction of image file size for processing, storage, and transmission. The quality of the image may be affected by the compression techniques used and the level of compression applied. Decompression is the process of retrieving compressed data and reassembling it so that it resembles its original form before compression. There are two types of compression:
Lossless compression is a process that reduces the storage space needed for an image file without loss of data. If an image has undergone lossless compression, it will be identical to the image before it was compressed. Primarily used with bitonal images.

Lossy compression is another process that reduces the storage space needed for an image file, but it discards information (information that is "redundant" and not perceptible to the human eye). If an image that has undergone lossy compression is decompressed, it will differ form the image before it was compressed, even though the difference may be difficult for the human eye to detect.

There are both standard and non-standard compression techniques available. In general, it is better to employ a compression technique that is supported by standards, non-proprietary, and maintained over time. In selecting a compression technique, it is necessary to consider the attributes of the original. Some compression techniques are designed to compress text, others are designed to compress pictures.

Continuous Tone An image where brightness appears consistent and uninterrupted. Each pixel in a continuous tone image file uses at least one byte each for its red, green, and blue values. This permits 256 density levels per color or more than 16 million mixture colors.

Contouring A visual effect in an image as a result of low brightness resolution which appears as bands of sharp, distinct, brightness change. Very similar to banding.

Contrast A measure of rate of change of brightness in an image.
-High contrast implies dark black and bright white content;
-Medium contrast implies a good spread from black to white;
-Low contrast implies a small spread of values from black to white.

CPU (Central Processing Unit) The chip in a computer where virtually all information is processed.

Cropping tool The cropping tool simulates the traditional method for cropping-that is, trimming photographs.

Cross-Platform software enables you to share information between computers running different operating systems, such as a Macintosh and Windows workstations.

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Data The generic name for anything input to, output from, or stored in a computer. All data must be in digital format.

Database is an organized collection of information stored on a computer. With Optix®, a database is an organized collection of electronic documents stored on a computer. The database is structured to facilitate the search and retrieval of information contained in the database. Database Field are placeholders for discrete bits of information in a database. For example, your last name would be typed in to a field for that purpose. The grouped contents of several fields together form a record.

Database Publishing enables you to publish a select group of documents from a large-scale document database to laptops and CD-ROMs, allowing you to create miniature, portable databases.

Database Query Screen is a computer generated form which allows you to search for information contained in the fields of a database. By entering information in pre-defined text fields, you instruct the computer to search the database for documents which contain that information. Some document management systems allow you to customize the query screens to accept information that is applicable to the database you wish to search.
Database Record is a collection of the contents of a related group of database fields.

Digital vs. analog information Digital data are represented by discrete values. Analog information is represented by ranges of values, and is therefore less precise. For example, you get clearer sound from an audio CD (which is digital) than from an audio cassette (which is analog). Computers use digital data.

Dedicated Lines Special cables used only for videoconferencing, usually within an office or school.

Default setting A preset parameter in computer programs which will be used unless changed by the operator.

Densitometer A tool used to measure the amount of light that is reflected or transmitted by an object.

Derived Image (Derivative Image) is an image that has been created from another image through some kind of automated process, usually involving a loss of information. Techniques used to create derived images include sampling to a lower resolution, using lossy compression techniques, or altering an image using image processing techniques.

Desktop Publishing Describes the digital process of combining text with visuals and graphics to create brochures, newsletters, logos, electronic slides and other published work with a computer.

Diffusion dithering A method of dithering that randomly distributes pixels instead of using a set pattern.

Digital A system or device in which information is stored or manipulated by on/off impulses, so that each piece of information has an exact or repeatable value (code).

Digital camera A device that captures an image on a CCD so it can be downloaded to and manipulated by a computer. It might also be called a filmless camera.

Digital Documents are documents that are stored on a computer. The documents may have been created on a computer, as with word-processing files and spreadsheets, or they may have been converted into digital documents by means of document imaging. Digital documents are also referred to as electronic documents.

Digital Image An image composed of pixels.

Digital Projector A device that connects to a computer via cabling to enable the computer monitor display to be enlarged and projected onto a screen.

Digital Scripts These are coding commands that turn complex digital imaging tasks into menu options that can be executed with a few steps. Scripts can be written for capture, post-processing, and application-related tasks.

Digital Zoom Allows the user to zoom in on a subject beyond the range provided by the optical zoom lens. Digital zooming crops the center of the digital picture and resizes the new cropped picture to the size of the selected resolution.

Digitization The process of converting analog information into digital format for use by a computer.

Diodes are light-sensitive electronic components used by the scanner during image capture. Diodes sense the presence or absence of light and create a digital signal that the computer then converts into pixel values.

Disc Term used to describe optical storage media (video disc, laser disc, compact disc), as opposed to magnetic storage systems.

Disk Term used to describe magnetic storage media (floppy disk, diskette, hard disk), as opposed to optical storage systems.

Dithering A method for simulating many colors or shades of gray with only a few. A limited number of same-colored pixels located close together is seen as a new color.

Document is a broadly used term that refers to word-processing files, e-mail messages, spreadsheets, database tables, faxes, business forms, images, or any other collection of organized data. Documents are also referred to as 'records.'

Document Imaging is the process by which print and film documents are fed into a scanner and converted into electronic documents. During the scanning process documents can be OCRed and indexed to insure quick retrieval at a later date.

Document Management Systems enable you to store documents electronically. This facilitates the process of retrieving, sharing, tracking, revising, and distributing documents and the information they contain. A complete Electronic Document Management System (EDMS) provides you with all the software and hardware required to insure that you maintain control over all your documents, both scanned images, and files that were created on a computer—like spreadsheets, word processing documents and graphics. A complete EDMS includes document imaging, OCR, text retrieval, workflow, and Computer Output to Laser Disk capabilities.

Document Retrieval is the process by which you can search and 'retrieve' an archived document from a database. This is done by entering information in a database query screen.

Download The transfer of files or other information from one piece of computer equipment to another.

DPI (Dots Per Inch) The measurement of resolution of a printer or video monitor based on dot density. For example, most laser printers have a resolution of 300 dpi, most monitors 72 dpi, most PostScript imagesetters 1200 to 2450 dpi. The measurement can also relate to pixels in an input file, or line screen dots (halftone screen) in a prepress output film.

Drag and Drop The process of moving text, graphics, or photos to different locations in a document.

Driver A software utility designed to tell a computer how to operate an external device. For instance, to operate a printer or a scanner, a computer will need a specific driver.

DTD Document Type Definition Documents are regarded as having types, just as other objects processed by computers do. The type of a document is defined by its constituent parts and structure. A DTD defines the structure of an SGML (Standard Generalized Markup Language) document.

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EAD - Encoded Archival Description. The EAD is an SGML (Standard Generalized Markup Language) DTD (Document Type Definition) intended to assist in the creation of electronic finding aids. Developed at UC-Berkeley, it is now maintained and supported as a standard by the Library of Congress and sponsored by the Society of American Archivists. The EAD can be used to represent complete archival structures, including hierarchies and associations. The kinds of functionality that EAD affords can also be implemented using Dublin Core, and it is also possible to migrate records from Dublin Core into the EAD format if necessary. More information on EAD is available at http://www.loc.gov/ead
EDMS is an acronym for Electronic Document Management System.
Effective ISO Analogous to film speed. A higher number means the camera sensor needs less light to make a good exposure. Higher numbers can help in situations of low light where flash may not be effective, e.g., large interiors in low light.

Electronic Documents are documents that are stored on a computer. The documents may have been created on a computer, as with word-processing files and spreadsheets, or they may have been converted into digital documents by means of document imaging. Electronic documents are also referred to as digital documents.

E-mail An abbreviation for electronic mail.

EPS (Encapsulated PostScript) A graphic file format developed by Aldus, Adobe, and Altsys to allow exchange of PostScript graphic files (image information) between application programs.

Ethernet An inexpensive, widely used local area network developed by Xerox, DEC and Intel Corp. for data transmission between interconnected computers. Ideally, it transmits data at 10 million bits per second (about a megabyte per second). Ethernet can be used with nearly every type of computer on the market today.

Exif (Exchangable image format) A file format used in digital cameras.

Export The process of transporting data from one computer, program, type of file format, or device to another.

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Fiber Optics An optical system that uses glass or transparent plastic fibers as light transmitting media.

File A collection of information, such as text, data, or images saved on a disk or hard drive.

File Format A type of program or data file. Some common image file formats include TIFF, PICT, and EPS.

File Server A computer that serves as the storage component of a local area network and permits users to share its hard disks, storage space, files, etc.

Film Recorder A device that is used to record a digital image onto photosensitive film.

Filters/Optical A glass or acetate sheet usually placed over a camera lens for changing characteristics of an image or to create a special effect.

Filters/Software A program that accepts data as input, transforms it in some manner, and then outputs the transformed data. For example, a software program such as PhotoShop can take blurry pictures and filter them to produce a clearer picture.

Final Image Resolution Generally speaking, the higher the resolution, the larger print you can make. Although print quality is affected by other factors as well, like exposure, color quality, output quality, etc. It's not just how many pixels, but what you do with them!

Firewire A very fast external bus that supports data transfer rates of up to 400 Mbps. Firewire was developed by Apple and falls under the IEEE 1394 standard. Other companies follow the IEEE 1394 but have names such as Lynx and I-link.

FITS (Functional Interpolating Transformation System) A format that contains that contains all data used to design and assemble extremely large files in a small, efficient mathematical structure.

Fixed Focus Lens Worry free camera operation. Fixed-focus lenses have their focus distance set to obtain good results within a wide range of distances without the need for a focus mechanism.

Flash A built-in flash supplies auxiliary light to supplement natural or available lighting conditions often resulting in better color, better exposure, and improved picture sharpness.

Flatbed Scanner An image capture device much like a photocopier. The object to be scanned is placed face-down on a glass plate. The CCD array passes beneath the glass.

FTP (File Transfer Protocol) An abbreviation for File Transfer Protocol and is a universal format for transferring files on the Internet.

Flash memory A type of memory chip that can retain data after the system has been turned off. Its advantage is that digital cameras with flash memory can have batteries go "dead" and yet retain image data.

Floppy Disk Typically, a removable computer storage medium consisting of a thin flexible plastic disk, coated with a magnetic material on both sides. The most common type, a 3.5-inch, is protected by a hard plastic case.

FPX Trade name for a new multi-resolution image file format jointly developed and introduced in June 1996 by Kodak, HP, Microsoft and Live Picture.

Frame One of the still pictures that make up a video.

Frame rate The number of frames that are shown or sent each second.

Full-Text Retrieval is a capability that enables you to search for documents stored in a database based on the text contained in the documents. It can be used in conjunction with index-based searching which relies on a description of the document entered by a scan operator.

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GIF Graphic Image File Format. A widely supported image storage format promoted by Compuserve for use on the web.

Gigabyte (GB) A measure of computer memory or disk space consisting of about one thousand million bytes (a thousand megabytes). The actual value is 1,073,741,824 bytes (1024 megabytes).

Graphical Route Developer Tools enable you to easily create, and modify, workflow routes by letting you 'draw' a workflow route on the screen, in much the way they would draw a picture with a computerized drawing program. In effect, users draw a map of how they want documents to flow through their organization.

Group-IV is a compression method designed by CCITT for use with Group IV fax machines. This method is optimized for compressing scanned text.

Gray Level The brightness of a pixel. The value associated with a pixel representing it's lightness from black to white. Usually defined as a value from 0 to 255, with 0 being black and 255 being white.

Gray Scale is a range of shades of gray in an image. Gray scales of scanners are determined by the number of grays, or values between black and white, that they can recognize and reproduce.

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Halftone Image An image reproduced through a special screen made up of dots of various sizes to simulate shades of gray in a photograph. Typically used for newspaper or magazine reproduction of images.

Hardware The 'nuts and bolts' of the computer, that includes the monitor, CPU, printers, disc drives, and etc.

HDTV High Definition Television. New video "standard" that will resolve 1,125 lines in the United States instead of the traditional 525 lines of the NTSC standard. In Europe and the Far East, the number of scan lines varies.

HTML- Hypertext Markup Language. An encoding format for linking and identifying electronic documents and used to deliver information on the World Wide Web. May be superceded by XML in the future.

Hyperlinks allow you to 'link' any document stored in a database with any other document. You can link a spreadsheet to an image, a database to a graphic, or a word processing file to a site on the World Wide Web. You can then navigate from one related document to another, simply by clicking on the hyperlinks.

Hue A term used to describe the entire range of colors of the spectrum; hue is the component that determines just what color you are using. In gradients, when you use a color model in which hue is a component, you can create rainbow effects.

Histogram A bar graph analysis tool that can be used to identify contrast and dynamic range image problems. Histograms are found in most software programs that are used to manipulate digital images.

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Image Capture - Using a scanner or other device to create a digital representation or electronic photograph of an image. The scanning process is often labor-intensive and costly, requiring a substantial investment in handling and processing original materials and their surrogate images. The current strategy is to capture an image at the highest resolution appropriate to the original, and store it off-line as an archival image on CD-ROM or magnetic tape. Techniques such as lossy compression and subsampling can then be used to create derivative images for use online. In the future, as the ability to deliver high-quality archival scans develops, it will be possible to place the archival scan online without cost of recapture. Scanning can be done in-house or contracted out to a vendor. Whether scanning is done in-house or outsourced, quality of the images can vary widely. Image specifications should be stated clearly in the contract with the vendor and sample images (at varying resolutions) of the materials to be scanned should be requested of the vendor prior to the start of the project.

Image Manipulation or Alteration refers to making changes (such as tonal adjustments, cropping, moire reduction, etc.) to an image using image processing software.

Image size describes the actual physical dimensions of an image, not the size it appears on a given display device.

Index refers to the information contained in an electronic document that enables you to retrieve it from a database. The index can include physical location information (e.g., where the document is stored) and document identification information (e.g., date archived, creator, and contents).

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JPEG (Joint Photographic Experts Group) is a standard image compression mechanism. JPEG compression is "lossy," meaning that the compression scheme sacrifices some image quality in exchange for a reduction in the file's size.

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Life Cycle refers to the period of time between when a document is archived and when it is destroyed.
Magnetic Disk Digital media that uses magnetic particles to store data. Both hard disks and floppy disks are magnetic disks.

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Metadata is data about data, or information known about the image in order to provide access to the image. Usually includes information about the intellectual content of the image, digital representation data, and security or rights management information.
Microfilm/Microfiche Scanner is a type of scanner that converts microfilm or microfiche documents into electronic documents.

Migration is the act of preserving the integrity of digital images by transferring them across hardware and software configurations and across subsequent generations of computer technology. Migration includes refreshment (copying digital files from one media to another) as a means of preservation and access. However, migration differs from refreshment in the sense that it is not always possible to make an exact copy of a database or even an image file as changes in hardware and software occur and still maintain compatibility with the new generation of technology.

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Network refers to two or more computers that have been linked together to enable them to communicate with each other, exchange information, and share resources.

Noise Data or unidentifiable marks picked up in the course of scanning or data transfer that do not correspond to the original.

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OCR (Optical Character Recognition) refers to the process by which scanned images are electronically "read" to convert them into editable text. This conversion is performed after scanning, and may output formatted text or text-only files (flat ASCII files). Text generated by OCR is often input into text search databases, allowing retrieval of the original scanned image based on its content.

Optical Disk discs that use tiny optically reflective particles to store data. A laser is used to read the reflective bits, and write data. Unlike CD-ROM, which is read-only, most optical disc systems are writable.

Optical Disk Jukebox is a piece of hardware that stores, and provides rapid access to multiple optical disks.

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Patch Card is a document that contains scanner and indexing instructions in the form of a bar code. Patch Cards can be inserted at specific points in a 'scan batch' where you desire new scanner or indexing settings to begin or end. Patch cards can instruct document imaging software to store a document in a specific database, assign the document an incremental sequence number, assign a job name, or record the scan date of a document. Patch cards are also capable of adjusting scanner settings and performing image enhancement operations such as 'deskew,' 'rotate,' and 'despeckle'.

Pixel is often referred to as dot, as in "dots per inch". "Pixel" is short for picture elements, which make up an image, similar to grains in a photograph or dots in a half-tone. Each pixel can represent a number of different shades or colors, depending on how much storage space is allocated for it. Pixels per inch (ppi) is sometimes the preferred term, as it more accurately describes the digital image.

Preservation (As it relates to scanning) refers to digitizing an original photograph, document, or three-dimensional object is only a method of preservation if the digital file becomes the access tool and the original is no longer available for use. Although high resolution scanning (i.e., scan at the highest resolution possible appropriate to the type of media you are scanning) is recommended for all materials in order to achieve the highest quality possible and to ensure that information held in the original is not lost in the scan. However, the digital file, as of yet, should not serve as a replacement of the original for preservation purposes.

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Quality Control describes techniques ensuring that high quality is maintained through various stages of a process. For example, quality control during image capture might include comparing the scanned image to the original and then adjusting colors or tonal values, or checking for artifacts.

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RAID (Redundant Array of Inexpensive Disks) is a storage technique that enables you to obtain increased storage reliability and performance by writing data to a connected series of disks referred to as a logical volume. Data reliability is achieved with error correction techniques or data duplication. Disk performance is achieved by parallel data transfers to a set of disks--this technique known as 'data striping.'

Record Retention Schedule is a form that details the categories of records an organization is required to store. It outlines the length of time different categories of records should be stored, and when they can be deleted.

Refreshment refers to the transfer of digital files to a new media on a regular basis. This is the most important part of an institution's long-term commitment to digitization. Technology is usually outdated by the time it hits the marketplace. The data we generate today must be retrievable five, fifty, and a hundred years from now. In order to ensure long-term access to the data, it must be transferred to the most recent and stable type of media storage. In a hundred years, it is very unlikely that any of the computers on our desks today will function. We must make sure that the data can be retrieved by future technology.

Resolution refers to the 'image-sharpness' of a document, usually measured In dots (or pixels) per inch (dpi). Documents can be scanned at various resolutions depending on your particular needs. The higher the resolution of a document, the greater the image-sharpness, and the larger the file size will be. Resolution also refers to the image-sharpness that printers and monitors are capable of reproducing.
Retention Period is the length of time documents must be stored and maintained to satisfy business or legal requirements.

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Scaleable refers to the ability to enlarge or reduce the size of an image. A document management system is said to be 'scaleable' if its capabilities can be increased to support additional users or platforms.

Scan Batch is a collection of documents that are fed into a scanner for the purpose of being converted into digital or electronic documents.
Scanner is a device for capturing a digital image. There are many types of scanners, such as flatbed scanners, drum scanners, slide scanners, and microfilm scanners.

Scanner Interface Board is a piece of hardware that enables software programs to communicate with various models of scanners.

Scanning see Image Capture

Scriptable and Recordable Software enables you to automate repetitive computer tasks. You can instruct a 'script' to open one program, carry out a task, close that program, open a new program, carry out a new task, and so on until the project is completed. Or, you can 'record' a series of steps as you perform them, and save those steps as a single script.

Semantic Network Technology is an underlying technology of sophisticated text retrieval software. It offers you a built-in 'dictionary' of 400,000 word meanings and over 1.6 million word relationships. It recognizes phrases like 'real estate' and 'kangaroo court' as single units of meaning, not individual words. It also recognizes words with multiple meanings such as 'concrete'. To choose the meaning appropriate for your query, you simply click on the meaning you intend. Semantic Network Technology helps to insure that you find the documents you are looking for quickly and easily.

SQL (Structured Query Language) is a database access language that originated on mainframes and minicomputers, and which is now popular on PCs.

Subsampling Using an algorithm to derive a lower-resolution image from a higher-resolution image.

Surrogate image A representation of the original image, used for study.

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Text Retrieval Software enables you to retrieve electronic documents from databases by entering 'key' words in a text search field. Documents containing the text you entered are retrieved from the database, and presented to you in a list ranked by relevancy.

TIFF (Tagged Image File Format) is an industry standard file format developed for the purpose of storing high-resolution bit-mapped, gray-scale, and color images.

TWAIN is a scanning interface standard developed to address the need for consistent, easy integration of scanners with document imaging programs. Software programs that are written to support the TWAIN standard are capable of controlling any TWAIN compliant scanner.

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URL refers to Uniform Resource Locator. A standard addressing scheme used to locate or reference files on the Internet. Used in World Wide Web documents to locate files. A URL gives the type of resource being used and the path to the file. The syntax used is: scheme://host.domain/path filename.

URN refers to Universal Resource Name/Number. A storage-independent scheme to name all resources on the Internet with a unique and fixed name. URNs are likely to supersede URLs for identification and referencing of networked resources.

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Workflow Software allows businesses to move electronic documents along a user-defined 'routing' path, from one workstation to the next, around a local or wide-area network. Once the document arrives at any given workstation, the receiver can add notations to, or modify, the document as they see fit. An insurance company might use workflow software to route claim forms through their organization. A user at one step might wish to review the forms and add a new document to the electronic 'package' before sending it to the next workstation. The next user might wish to add several notations to the forms before sending it on to the final workstation for approval. The route can be as simple or as complex as a business process requires.

World Wide Web (WWW) is an interconnected network of electronic hypermedia documents available on the Internet. WWW documents are marked up in HTML. Cross references or hyperlinks between documents are recorded in the form of URLs.

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Zooming describes enlarging a portion of a digital image in order to see it more clearly or make it easier to alter.

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Definitions taken from The Nebraska State Historical Society Glossary of Digital Imaging Terms and "A Glossary of Scanning Terms" from Preservation Resources.

Kodak also has a Glossary of digital imaging terms