A cable modem is an external device that hooks up to your computer and
instead of getting an internet connection through your telephone wire (or
another system), you get a connection through your cable network (same
place your cable TV connection comes from). Cable modems translate radio
frequency (RF) signals to and from the cable plant into Internet Protocol (IP),
the communications protocol spoken by all computers connected to the
Internet. Cable modems are designed to take advantage of the broadband cable infrastructure enabling peak connection speeds over 100 times faster
than traditional dial-up connections.
A web hosting company (usually an ISP) leases server space and web services to companies and individuals who wish to present a web or e-commerce presence but do not wish to maintain their own servers. The servers are connected to the same fast internet backbone as the ISP. Cost structures are determined by the amount and complexity of services offered such as Scripting Tools, SQL Databases, Credit Card Processing, etc.
A very fast version of SCSI (Small Computer Systems Interface) which can have an 8-bit or 16-bit bus. The 8-bit version has a 50-pin adapter, transfers data at a rate of 20 megabytes per second, and can connect a maximum of 8 devices. The 16-bit version has a 68-pin adapter, transfers data at 20 to 40 megabytes per second, and can connect up to 16 devices.
Universal Automatic Computer. The world's first electronic general purpose data processing computer, introduced in 1951, and used by the U.S. Census Bureau. UNIVAC 1 was designed and built by the Eckert-Mauchly Computer Corporation, which was later acquired by Remington Rand.
(UUCP). A UNIX protocol that makes it possible to copy a file from one UNIX computer to another via a telephone line or direct connection. It is used for Usenet news and electronic mail. Unlike TCP/IP, UUCP requires that a session be established between the two computers in order to transfer files.
A computer program that is not a virus or worm but that makes copies of itself every time it is run, which eventually crashes the system. The original "wabbit" appeared in the late 1970s.
|Universal Naming Convention|
(UNC) Also called Uniform Naming Convention. A convention for specifying directories, servers, and other resources on a network, using two slashes // or backslashes \ to indicate the name of the server, and one slash to indicate the path or shared directory within the computer, in this format: \servershare or //server/share.
Users' Network. A giant public bulletin board system on the Internet for news and electronic mail. Usenet was started in 1979 by graduate students at Duke University and the University of North Carolina, using the UUCP communications protocol. It now has over 12,000 discussion areas which cover every imaginable topic are read by millions of people all over the world. Messages and news articles are posted and users respond by email. In hot discussion areas, hundreds of messages a day may be posted. Types of Usenet groups are comp (about computers), news (about newsgroups), rec (on sports and hobbies), sci (science), soc (social), talk (discussions), misc (miscellaneous), and alt (alternative newsgroups).
A small helper program. Utilities are distinguished from application programs, which are used to do the main work of the computer (such as word processing, accounting, CAD), and system programs, which control the computer and run application programs. Some examples of utilities are screensavers, font managers, compression programs, and file finders.
A UNIX program that encodes binary data, 8-bit text files, and some other file formats into 7-bit ASCII files for transmission over the Internet and via e-mail. It was originally used with UUCP. The uudecode program converts the files back into their original format. Uuencoded files have .uu or .uue as a suffix.
A way of representing pictures by designating coordinates and drawing lines or geometric shapes in relation to them. Vector graphics are different from raster graphics, in which an image is stored as a collection of pixels. In vector graphics, the image is saved as a file containing instructions for drawing it. One advantage of vector graphics over raster graphics is that a picture can be enlarged or reduced without losing quality. Another difference is that in vector graphics, the elements of a picture (circles, squares, etc.) remain independent objects which can be edited and moved around, whereas in raster graphics, once the elements are drawn they become part of the overall pattern of pixels. A vector graphics image also requires less memory than a raster graphics image, which requires a specific memory location for each pixel.
|vertical scan rate|
(VSR). The maximum number of frames per second that a computer monitor can display, expressed in hertz. Too low a scan rate causes a flickering screen which is hard on the eyes. Each frame begins with the electron gun at the upper left corner of the screen. An electron beam is scanned horizontally across the screen, making one line; it moves down slightly to make the next line, and continues until it reaches the bottom. The electron gun returns to the upper left corner to begin the next frame.
A benchmark for measuring the performance of Web server software by running different Web server packages on the same server hardware or by running a given Web server package on different hardware platforms. WebBench has both static test suites, which test only HTML pages, and dynamic tests suites, which use a combination of common gateway interface (CGI) scripts and static requests.
Electronic commerce; the use of computers and electronic communications in business transactions. E-commerce may include the use of electronic data interchange (EDI), electronic money exchange, Internet advertising, Web sites, online databases, computer networks, and point-of-sale (POS) computer systems.
A variable, on the other hand, is the actual
instantiation (the memory storage of data values being manipulated in the
program) of that data-type at runtime or simply the actual memory that
is allocated at runtime.
Â Â Â Â Â Â Â Â Â Â Â Int aPrimitiveInt = 24;
where, 24 is the variable,
or in this case, the actual contents stored in memory.
An identifier is the name and associated data-type
that identifies a variable in a Java source file or more simply, the name of
the variable that is in the source code for the program.
where, aPrimitiveInt is the
name and int is the data type
|Resource Description Framework|
(RDF). A specification being developed by the W3C to provide an infrastructure to support metadata on the Internet and WWW. For example, using RDF, data about a Web page could be divided into a main subject, secondary subjects, date of creation, name of author, etc. Putting this data into fields (which can be indicated by XML tags) would allow search engines to do smarter searches. A search engine could find, for example, all documents written by a particular author before a given date, on a specific subject. RDF does not specify names for the fields, but defines the syntax for how different fields relate to Web pages and to one another. Other examples of how RDF could be used include sitemaps, content ratings, digital libraries, and distributed authoring.
|RFID: Radio frequency identification|
Radio frequency identification (RFID) is a system for tagging and identifying mobile objects such as store merchandise, postal packages and sometimes living organisms (like pets). RFID uses low-powered radio transmitters to read data stored in a transponder (tag) at distances ranging from one inch to 100 feet. RFID tags are used to track assets, manage inventory and authorize payments, and they increasingly serve as electronic keys for everything from autos to secure facilities. RFID works using small (sometimes smaller than a fingernail) pieces of hardware called RFID chips. These chips feature an antenna to transmit and receive radio signals. So-called passive RFID chips do not have a power source, but active RFID chips do. RFID chips may be attached to objects, or in the case of some passive RFID systems, injected into objects.
PHP 5.0 is the latest release of the server-side scripting solution already in use on over 70,000 World Wide Web sites. This all-new version of the popular scripting language includes support for all major operating systems (Windows 95/NT, most versions of Unix, and Macintosh) and webhosting servers (including Apache, Netscape servers, WebSite Pro, and Microsoft Internet Information Server). PHP 3.0 also supports a wide range of databases, including Oracle, Sybase, Solid, MySQ, mSQL, and PostgreSQL, as well as ODBC data sources. New features include persistent database connections, support for the SNMP and IMAP protocols, and a revamped C API for extending the language with new features.
Voice search is a speech recognition technology that allows users to search by saying terms aloud rather than typing them into a search field. Traditional voice search applications, such as Google Mobile App with Voice and Vlingo for iPhone, rely on speech recognition programs.
|Astronomical Markup Language|
(AML). A standardized format for exchange of metadata related to astronomy. This language will enhance the ability of astronomers to retrieve scientific data, and make it possible for humans and intelligent agents to use the same information. Humans can view AML documents by means of a Java AML browser; intelligent agents can use an Extensible Markup Language (XML) parser.
|Bank Internet Payment System|
|Digital Signal Processing|
(DSP). Using computers to process signals such as sound, video, and other analog signals which have been converted to digital form. Some uses of DSP are to decode modulated signals from modems, to process sound, video, and images in various ways, and to understand data from sonar, radar, and seismological readings.
(DC). A project to create a structure for categorizing electronic documents in a similar way to the sorting of library books in a card catalogue. The Dublin Core schema has fifteen fields that give all the basic information about an electronic document, including the title, subject, creator, publisher, and date of creation. Describing documents in this way will make it possible to use search engines more effectively. See also XML, RDF, and metadata.
|Eight to Fourteen Modulation|
(EFM). In magnetic media, a byte commonly has 8 bits. Optical media such as CD-ROM discs uses a 14-bit byte, a modification necessary because of the way data is stored and read with lasers, using the pits (indentations) and lands (spaces between indentations) on the disc. In transferring from magnetic to optical media, the 8-bit byte has to be modulated to a 14-bit byte. When the computer reads the CD-ROM, an interface card demodulates the 14- bit optical code back to 8-bit code.