SAA ~ server error
A/B Switch box ~ America On-line AMI BIOS ~ Arithmetic Operation ARP ~ AVI Backbone ~ Bit Image Bit Map ~ Boot Disk Boot Drive ~ Bytes Per Inch C++ ~ Carrier Frequency carrier system ~ certification CGI ~ Chooser extension cipher ~ Clipper Chip clock ~ color color bits ~ communications satellite communications server ~ computer security CON ~ copy copy program ~ cycle time daemon ~ defragmentation demand paging ~ digitize DikuMUD ~ disk disk buffer ~ Document Style Semantics and Specification Language document window ~ dynamic Web page Easter egg ~ erase erase head ~ ezine F2F ~ finger2 firewall ~ font suitcase footer ~ FYI Game Control Adapter ~ GUI HAL ~ hot key1 hot key2 ~ Hz i486DX ~ internal modem internet ~ ISO 9660 ISO/OSI model ~ just-in-time K1 ~ knowledge base L1 cache ~ LU luggable computer ~ LZW compression MAC ~ MILNET mime ~ msec MTBF ~ MYOB named anchor ~ network drive Network File System ~ number crunching object ~ overwrite mode P5 ~ PC/XT keyboard PDA ~ pipeline processing piracy ~ preventive maintenance preview ~ pwd quasi-language ~ QWERTY keyboard R&D ~ registration marks Registry ~ RFI RF shielding ~ run-time library SAA ~ server error server push-pull ~ soft return software ~ style sheet stylus ~ System T1 ~ ToggleKeys token ~ typography UART ~ uupc V.120 ~ view2 viewer ~ VxD w3 ~ WinG WINS ~ WWW X.25 ~ X Windows Yahoo! ~ yotta- Z39.50 standard ~ Zulu time
SAA
n. Acronym for Systems Application Architecture. An IBM-developed standard for the appearance and operation of application software that will give programs written for all IBM computers--mainframe computers, minicomputers, and personal computers--a similar look and feel. SAA defines how an application interfaces with both the user and the supporting operating system. True SAA-compliant applications are compatible at the source level (before being compiled) with any SAA-compliant operating system--provided the system is capable of furnishing all the services required by the application.
safe mode
n. In some versions of Windows, such as Windows 95, a boot mode in which most drivers and peripherals are disconnected to allow the user to correct some problem with the system. This will occur if the system was not shut down properly or if the system failed to complete a boot-up. See also boot1.
sans serif
adj. Literally, "without stroke"; describes any typeface in which the characters have no serifs (the short lines or ornaments at the upper and lower ends of the strokes). A sans serif typeface usually possesses a more straightforward, geometric appearance than a typeface with serifs and typically lacks the contrast between thick and thin strokes found in serif faces. Sans serif typefaces are used more frequently in display type, such as headlines, than in blocks of text. Compare serif1.
SAP
n. See Service Advertising Protocol.
SAPI
n. Acronym for Speech Application Programming Interface. A feature in Windows 95 and Windows NT that allows applications to include speech recognition or convert text to speech. Also called Speech API. See also speech recognition.
satellite
n. See communications satellite.
satellite computer
n. A computer that is connected to another computer, with which it interacts over a communications link. As its name indicates, a satellite computer is of lesser "stature" than the main, or host, computer; the host controls either the satellite itself or the tasks the satellite performs. See also remote communications.
saturation
n. 1. In a switching device or amplifier, the fully conducting state. At saturation, the device is passing the maximum possible current. The term is most commonly used with reference to circuits containing bipolar or field-effect transistors. 2. In color graphics and printing, the amount of color in a specified hue, often specified as a percentage. See also HSB.
save
vb. To write data (typically a file) to a storage medium, such as a disk or tape.
scalable
adj. Of or relating to the characteristic of a piece of hardware or software that makes it possible for it to expand to meet future needs. For example, a scalable network allows the network administrator to add many additional nodes without the need to redesign the basic system.
scalable font
n. Any font that can be scaled to produce characters in varying sizes. Examples of scalable fonts are screen fonts in a graphical user interface, stroke fonts (such as Courier) and outline fonts common to most PostScript printers, TrueType fonts, and the method for screen font definition used in Macintosh System 7. In contrast, most text-based interfaces and printing devices (such as daisy-wheel printers) offer text in only one size. See also outline font, PostScript font, screen font, stroke font, TrueType.
scalable parallel processing
n. Multiprocessing architectures in which additional processors and additional users can easily be added without excessive increases in complexity and loss of performance. Acronym: SPP.
scale1
n. A horizontal or vertical line on a graph that shows minimum, maximum, and interval values for the data plotted.
scale2
vb. 1. To enlarge or reduce a graphic display, such as a drawing or a proportional character font, by adjusting its size proportionally. 2. To alter the way in which values are represented so as to bring them into a different range--for example, to change linear feet to quarter inches on a blueprint drawing of a house. 3. In programming, to determine the number of digits occupied by fixed-point or floating-point numbers. See also fixed-point notation, floating-point number.
scan
vb. 1. In television and computer display technologies, to move an electron beam across the inner surface of the screen, one line at a time, to light the phosphors that create a displayed image. 2. In facsimile and other optical technologies, to move a light-sensitive device across an image-bearing surface such as a page of text, converting the light and dark areas on the surface to binary digits that can be interpreted by a computer.
scanner
n. An optical input device that uses light-sensing equipment to capture an image on paper or some other subject. The image is translated into a digital signal that can then be manipulated by optical character recognition (OCR) software or graphics software. Scanners come in a number of types, including flatbed (scan head passes over a stationary subject), feed (subject is pulled across a stationary scan head), drum (subject is rotated around a stationary scan head), and handheld (user passes device over a stationary subject).
scatter diagram
n. A graph consisting of points whose coordinates represent values of data, often used to illustrate a correlation between one or more variables and a test group. Also called point chart, point diagram.
schedule
vb. To program a computer to perform a specified action at a specified time and date.
scheduler
n. An operating-system process that starts and ends tasks (programs), manages concurrently running processes, and allocates system resources. Also called dispatcher.
schema
n. A description of a database to a database management system (DBMS) in the language provided by the DBMS. A schema defines aspects of the database, such as attributes (fields) and domains and parameters of the attributes.
schematic
n. A diagram that shows a circuit's components and the connections between them using lines and a set of standard symbols to represent various electronic components.
scope
n. 1. In programming, the extent to which an identifier, such as a constant, data type, variable, or routine, can be referenced within a program. Scope can be global or local. Scope can also be affected by redefining identifiers, such as by giving the same name to both a global variable and a local variable. See also block1 (definition 3), global, local. 2. In electronics, slang for oscilloscope. See also oscilloscope.
scrambler
n. A device or program that reorders a signal sequence in order to render it indecipherable. See also encryption.
scrap
n. An application or system file maintained for storing data that has been marked for movement, copying, or deletion. See also clipboard (definition 1).
scrapbook
n. 1. A file in which a series of text and graphical images can be saved for subsequent use. 2. A Macintosh system file that can hold a number of text and graphical images for later use. Compare clipboard (definition 1).
scratch1
n. A memory region or file used by a program or operating system to hold work in progress temporarily. Created and maintained usually without the end user's knowledge, the scratch is needed only until the current session is terminated, at which time the data is saved or discarded. Also called scratch file. See also temporary file. Compare scrap.
scratch2
vb. To erase or discard data.
screen dump
n. A duplicate of a screen image; essentially, a "snapshot" of the screen that is either sent to a printer or saved as a file.
screen font
n. A typeface designed for display on a computer monitor screen. Screen fonts often have accompanying PostScript fonts for printing to PostScript-compatible printers. See also derived font, intrinsic font. Compare PostScript font, printer font.
screen pitch
n. A measurement of a computer monitor's screen density, representing the distance between phosphors on the display. The lower the number, the more detail can be displayed clearly. For example, a .28-dot-pitch screen has better resolution than one with .32. See also phosphor.
screen saver
n. A utility that causes a monitor to blank out or display a certain image after a specified amount of time passes without the keyboard being touched or the mouse being moved. Touching a key or moving the mouse deactivates the screen saver. Screen savers were originally used to prevent images from becoming permanently etched on a monitor's screen. Although modern monitors are not susceptible to this problem, screen savers remain popular for their decorative and entertainment value.
screen shot
n. An image that shows all or part of a computer display. The illustration shown here as well as entries alert box, cell, and menu bar, for example, are screen shots.
script
n. A program consisting of a set of instructions to an application or utility program. The instructions usually use the rules and syntax of the application or utility. See also macro.
scripting language
n. A simple programming language designed to perform special or limited tasks, sometimes associated with a particular application or function. An example of a scripting language is Perl. See also Perl, script.
scroll
vb. To move a document or other data in a window in order to view a particular portion of the document. Scrolling may be controlled by the mouse, arrow keys, or other keys on the keyboard. See also scroll bar.
scroll bar
n. In some graphical user interfaces, a vertical or horizontal bar at the side or bottom of a display area that can be used with a mouse for moving around in that area. Scroll bars often have four active areas: two scroll arrows for moving line by line, a sliding scroll box for moving to an arbitrary location in the display area, and gray areas for moving in increments of one window at a time.
SCSI
n. Acronym for Small Computer System Interface, a standard high-speed parallel interface defined by the X3T9.2 committee of the American National Standards Institute (ANSI). A SCSI interface is used to connect microcomputers to SCSI peripheral devices, such as many hard disks and printers, and to other computers and local area networks. Compare ESDI, IDE.
SCSI-2
n. An enhanced ANSI standard for SCSI (Small Computer System Interface) buses. Compared with the original SCSI standard (now called SCSI-1), which can transfer data 8 bits at a time at up to 5 MB per second, SCSI-2 offers increased data width, increased speed, or both. A SCSI-2 disk drive or host adapter can work with SCSI-1 equipment at the older equipment's maximum speed. See also Fast SCSI, Fast/Wide SCSI, SCSI, Wide SCSI. Compare UltraSCSI.
SCSI bus
n. A parallel bus that carries data and control signals from SCSI devices to a SCSI controller. See also bus, controller, SCSI device.
SCSI chain
n. A set of devices on a SCSI bus. Each device (except the host adapter and the last device) is connected to two other devices by two cables, forming a daisy chain. See also daisy chain, SCSI.
SCSI connector
n. A cable connector used to connect a SCSI device to a SCSI bus. See also bus, connector (definition 1), SCSI device.
SCSI device
n. A peripheral device that uses the SCSI standard to exchange data and control signals with a computer's CPU. See also peripheral, SCSI.
SCSI ID
n. The unique identity of a SCSI device. Each device connected to a SCSI bus must have a different SCSI ID. A maximum of eight SCSI IDs can be used on the same SCSI bus. See also bus, SCSI device.
SCSI network
n. A set of devices on a SCSI bus, which acts like a local area network. See also SCSI.
SCSI port
n. 1. A SCSI host adapter within a computer, which provides a logical connection between the computer and all of the devices on the SCSI bus. See also SCSI. 2. A connector on a device for a SCSI bus cable. See also SCSI.
SDK
n. Acronym for software developer's kit. See developer's toolkit.
SDLC
n. Acronym for Synchronous Data Link Control, the data transmission protocol most widely used by networks conforming to IBM's Systems Network Architecture (SNA). SDLC is similar to the HDLC (High-level Data Link Control) protocol developed by the International Organization for Standardization (ISO). See also HDLC.
SDRAM
n. See synchronous DRAM.
seamless integration
n. The favorable result that occurs when a new hardware component or program blends smoothly into the overall operation of the system. It is usually the result of thoughtful design and programming.
search1
n. The process of seeking a particular file or specific data. A search is carried out by a program through comparison or calculation to determine whether a match to some pattern exists or whether some other criteria have been met. See also binary search, hash search, linear search, search and replace, wildcard character.
search2
vb. 1. To look for the location of a file. 2. To seek specific data within a file or data structure. See also replace.
search algorithm
n. An algorithm designed to locate a certain element, called the target, in a data structure. See also algorithm, binary search, hash search, linear search.
search and replace
n. A common process in applications such as word processors in which the user specifies two strings of characters. The process finds instances of the first string and replaces them with the second string.
search criteria
n. The terms or conditions that a search engine uses to find items in a database. See also search engine.
search engine
n. 1. A program that searches for key words in documents or in a database. 2. On the Internet, a program that searches for keywords in files and documents found on the World Wide Web, newsgroups, Gopher menus, and FTP archives. Some search engines are used for a single Internet site, such as a dedicated search engine for a Web site. Others search across many sites, using such agents as spiders to gather lists of available files and documents and store these lists in databases that users can search by keyword. Examples of the latter type of search engine are Lycos, AliWeb, and Excite. Most search engines reside on a server. See also agent (definition 2), FTP, Gopher, newsgroup, spider, World Wide Web.
search key
n. 1. The particular field (or column) of the records to be searched in a database. See also primary key, secondary key. 2. The value that is to be searched for in a document or any collection of data.
search string
n. The string of characters to be matched in a search--typically (but not necessarily) a text string.
seat1
n. One workstation or computer, in the context of software licensing on a per-seat basis. See also license agreement, workstation (definition 1).
seat2
vb. To insert a piece of hardware fully and position it correctly in a computer or affiliated equipment, as in seating a single inline memory module (SIMM) in its socket.
secondary channel
n. A transmission channel in a communications system that carries testing and diagnostic information rather than actual data. Compare primary channel.
secondary service provider
n. An Internet service provider that provides a Web presence but not direct connectivity. See also ISP.
secondary storage
n. Any data storage medium other than a computer's random access memory (RAM)--typically tape or disk. Compare primary storage.
sector
n. A portion of the data storage area on a disk. A disk is divided into sides (top and bottom), tracks (rings on each surface), and sectors (sections of each ring). Sectors are the smallest physical storage units on a disk and are of fixed size; typically, they are capable of holding 512 bytes of information apiece.
secure channel
n. A communications link that has been protected against unauthorized access, operation, or use by means of isolation from the public network, encryption, or other forms of control. See also encryption.
Secure Electronics Transactions protocol
n. Protocol for conducting secure transactions on the Internet, the result of a joint effort by GTE, IBM, MasterCard, Microsoft, Netscape, SAIC, Terisa Systems, VeriSign, and Visa. Acronym: SET.
secure site
n. A Web site having the capability of providing secure transactions, ensuring that credit card numbers and other personal information will not be accessible to unauthorized parties.
Secure Sockets Layer
n. A proposed open standard developed by Netscape Communications for establishing a secure communications channel to prevent the interception of critical information, such as credit card numbers. The primary purpose of Secure Sockets Layer is to enable secure electronic financial transactions on the World Wide Web, although it is designed to work with other Internet services as well. This technology, which uses public key encryption, is incorporated into the Netscape Navigator Web browser and Netscape's commerce servers. See also commerce server, open standard, public key encryption. Compare S-HTTP. Acronym: SSL.
Secure Transaction Technology
n. The use of the Secure Sockets Layer (SSL), Secure HTTP (S-HTTP), or both in online transactions, such as form transmission or credit card purchases. See also Secure Sockets Layer, S-HTTP. Acronym: STT.
secure wide area network
n. A set of computers that communicate over a public network, such as the Internet, but use security measures, such as encryption, authentication, and authorization, to prevent their communications from being intercepted and understood by unauthorized users. See also authentication, authorization, encryption, virtual private network (definition 1). Acronym: S/WAN.
security
n. Protection of a computer system and its data from harm or loss. A major focus of computer security, especially on systems that are accessed by many people or through communications lines, is the prevention of system access by unauthorized individuals.
security kernel
n. An operating-system kernel that is protected from unauthorized use. See also kernel.
security log
n. A log, generated by a firewall or other security device, that lists events that could affect security, such as access attempts or commands, and the names of the users involved. See also firewall, log (definition 1).
seek
n. The process of moving the read/write head in a disk drive to the proper site, typically for a read or write operation.
seek time
n. The time required to move a disk drive's read/write head to a specific location on a disk. See also access time (definition 2).
segment
n. A section of a program that, when compiled, occupies a contiguous address space and that is usually position independent; that is, it can be loaded anywhere in memory. With Intel-based microcomputers, a native-mode segment is a logical reference to a 64-KB contiguous portion of RAM in which the individual bytes are accessed by means of an offset value. Collectively, the segment:offset values reference a single physical location in RAM. See also overlay1 (definition 1), real mode, segmentation.
segmentation
n. The act of breaking up a program into several sections, or segments. See also segment.
segmented addressing architecture
n. A memory-access technique typified by Intel 80x86 processors. Memory is divided into 64-KB segments in this architecture for addressing locations under the 16-bit address scheme; 32-bit schemes can address memory in segments as large as 4 GB. Also called segmented instruction addressing, segmented memory architecture. Compare linear addressing architecture.
segmented address space
n. An address space that is logically divided into chunks called segments. To address a given location, a program must specify both a segment and an offset within that segment. (The offset is a value that references a specific point within the segment, based on the beginning of the segment.) Because segments may overlap, addresses are not unique; there are many logical ways to access a given physical location. The Intel 80x86 real-mode architecture is segmented; most other microprocessor architectures are flat. See also segment. Compare flat address space.
self-extracting file
n. An executable program file that contains one or more compressed text or data files. When a user runs the program, it uncompresses the compressed files and stores them on the user's hard drive.
self-test
n. A set of one or more diagnostic tests that a computer or peripheral device (such as a printer) performs on itself. See also power-on self test.
semiconductor
n. A substance, commonly silicon or germanium, whose ability to conduct electricity falls between that of a conductor and that of a nonconductor (insulator). The term is used loosely to refer to electronic components made from semiconductor materials.
send
n. To transmit a message or file through a communications channel.
send statement
n. In SLIP and PPP scripting languages, a statement that tells the program that dials an Internet service provider's number (a dialer program) to send certain characters. See also ISP, PPP, scripting language, SLIP.
sensor glove
n. A hand-worn computer input device for virtual-reality environments. The glove translates finger movements by the user to commands for manipulating objects in the environment. Also called data glove. See also virtual reality.
serial
adj. One by one. For example, in serial transmission, information is transferred one bit at a time; a serial computer has only one arithmetic logic unit, which must execute the whole program one step at a time. Compare parallel (definition 3).
Serial Infrared
n. A system developed by Hewlett-Packard for transmitting data between two devices up to 1 meter apart using an infrared light beam. Infrared ports on the receiving and the sending devices must be aligned. Generally, Serial Infrared is used with laptops and many notebook computers, as well as with peripherals such as printers. See also infrared port. Acronym: SIR.
SerialKeys
n. A feature of Windows 95 that, in conjunction with a communications aid interface device, allows keystrokes and mouse controls to be accepted through a computer's serial port.
serial mouse
n. A pointing device that attaches to the computer through a standard serial port. See also mouse. Compare bus mouse.
serial port
n. An input/output location (channel) that sends and receives data to and from a computer's central processing unit or a communications device one bit at a time. Serial ports are used for serial data communication and as interfaces with some peripheral devices, such as mice and printers.
serial port adapter
n. An interface card or device that either provides a serial port or converts a serial port to another use. See also adapter, serial port.
serial printer
n. A printer connected to the computer via a serial interface (commonly RS-232-C or compatible). Connectors for this type of printer vary widely, which is one reason they are less popular than parallel printers among those who use IBM and IBM-compatible PCs. Serial printers are standard for Apple computers. See also DB connector, serial, serial transmission. Compare parallel printer.
serial transmission
n. The transfer of discrete signals one after another. In communications and data transfer, serial transmission involves sending information over a single line one bit at a time, as in modem-to-modem connections. Compare parallel transmission.
serif1
adj. Marked by the use of serifs. For example, Goudy is a serif typeface, whereas Helvetica is a sans serif typeface. See also serif2. Compare sans serif.
serif2
n. Any of the short lines or ornaments at the ends of the strokes that form a typeface character.
server
n. 1. On a local area network (LAN), a computer running administrative software that controls access to the network and its resources, such as printers and disk drives, and provides resources to computers functioning as workstations on the network. 2. On the Internet or other network, a computer or program that responds to commands from a client. For example, a file server may contain an archive of data or program files; when a client submits a request for a file, the server transfers a copy of the file to the client. See also client/server architecture. Compare client (definition 3).
server-based application
n. A program that is shared over a network. The program is stored on the network server and can be used at more than one client machine at a time.
server cluster
n. A group of independent computers that work together as a single system. A server cluster presents the appearance of a single server to a client.
server error
n. A failure to complete a request for information through HTTP that results from an error at the server rather than an error by the client or the user. Server errors are indicated by HTTP status codes beginning with 5. See also HTTP, HTTP status codes.
A/B Switch box ~ America On-line AMI BIOS ~ Arithmetic Operation ARP ~ AVI Backbone ~ Bit Image Bit Map ~ Boot Disk Boot Drive ~ Bytes Per Inch C++ ~ Carrier Frequency carrier system ~ certification CGI ~ Chooser extension cipher ~ Clipper Chip clock ~ color color bits ~ communications satellite communications server ~ computer security CON ~ copy copy program ~ cycle time daemon ~ defragmentation demand paging ~ digitize DikuMUD ~ disk disk buffer ~ Document Style Semantics and Specification Language document window ~ dynamic Web page Easter egg ~ erase erase head ~ ezine F2F ~ finger2 firewall ~ font suitcase footer ~ FYI Game Control Adapter ~ GUI HAL ~ hot key1 hot key2 ~ Hz i486DX ~ internal modem internet ~ ISO 9660 ISO/OSI model ~ just-in-time K1 ~ knowledge base L1 cache ~ LU luggable computer ~ LZW compression MAC ~ MILNET mime ~ msec MTBF ~ MYOB named anchor ~ network drive Network File System ~ number crunching object ~ overwrite mode P5 ~ PC/XT keyboard PDA ~ pipeline processing piracy ~ preventive maintenance preview ~ pwd quasi-language ~ QWERTY keyboard R&D ~ registration marks Registry ~ RFI RF shielding ~ run-time library SAA ~ server error server push-pull ~ soft return software ~ style sheet stylus ~ System T1 ~ ToggleKeys token ~ typography UART ~ uupc V.120 ~ view2 viewer ~ VxD w3 ~ WinG WINS ~ WWW X.25 ~ X Windows Yahoo! ~ yotta- Z39.50 standard ~ Zulu time