A B C D E F G H I J K L M N O P Q R S T U V W X Y Z.

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SCRIPTING LANGUAGE: Series of programmed commands that designate how one computer communicates with another computer.

SEARCH ENGINE: On the Internet, a search engine has three parts:
A spider (also called a "crawler" or a "bot") that goes to every page or representative pages on every Web site that wants to be searchable and reads it, using hypertext links on each page to discover and read a site's other pages
A program that creates a huge index (sometimes called a "catalog") from the pages that have been read
A program that receives your search request, compares it to the entries in the index, and returns results to you
An alternative to using a search engine is to explore a structured directory of topics. Yahoo, which also lets you use its search engine, is the most widely-used directory on the Web. A number of Web portal sites offer both the search engine and directory approaches to finding information.
Different Search Engine Approaches
Major search engines such as Yahoo, AltaVista, Lycos, and Google index the content of a large portion of the Web and provide results that can run for pages - and consequently overwhelm the user.
Specialized content search engines are selective about what part of the Web is crawled and indexed. For example, TechTarget sites for products such as the AS/400 (http://www.search400.com) and Windows NT (http://www.searchnt.com) selectively index only the best sites about these products and provide a shorter but more focused list of results.
Ask Jeeves (http://www.askjeeves.com) provides a general search of the Web but allows you to enter a search request in natural language, such as "What's the weather in Seattle today?"
Special tools such as WebFerret (from http://www.softferret.com) let you use a number of search engines at the same time and compile results for you in a single list.
Individual Web sites, especially larger corporate sites, may use a search engine to index and retrieve the content of just their own site. Some of the major search engine companies license or sell their search engines for use on individual sites.
Where to Search First
The last time we looked, the Open Directory Project listed 370 search engines available for Internet users. There are about ten major search engines, each with its own anchor Web site (although some have an arrangement to use another site's search engine or license their own search engine for use by other Web sites). Some sites, such as Yahoo, search not only using their search engine but also give you the results from simultaneous searches of other search indexes. Sites that let you search multiple indexes simultaneously include:
Yahoo (http://www.yahoo.com)
search.com (http://search.com)
EasySearcher (http://www.easysearcher.com)
Yahoo first searches its own hierarchically-structured subject directory and gives you those entries. Then, it provides a few entries from the AltaVista search engine. It also launches a concurrent search for entries matching your search argument with six or seven other major search engines. You can link to each of them from Yahoo (at the bottom of the search result page) to see what the results were from each of these search engines.

SECURITY CERTIFICATE: A chunk of information (often stored as a text file) that is used by the SSL protocol to establish a secure connection.
Security Certificates contain information about who it belongs to, who it was issued by, a unique serial number or other unique identification, valid dates, and an encrypted "fingerprint" that can be used to verify the contents of the certificate.
In order for an SSL connection to be created both sides must have a valid Security Certificate

SELF EXTRACTING ARCHIVE: An archived file with the filename extension .exe, indicating that when downloaded and run, it will be extracted by the decompressing program around it, without user intervention, or the need to have additional decompression software.

SERVER: 1) In general, a server is a computer program that provides services to other computer programs in the same or other computers.
2) The computer that a server program runs in is also frequently referred to as a server (though it may contain a number of server and client programs).
3) In the client/server programming model, a server is a program that awaits and fulfils requests from client programs in the same or other computers. A given application in a computer may function as a client with requests for services from other programs and a server of requests from other programs.
Specific to the Web, a Web server is the computer program (housed in a computer) that serves requested HTML pages or files. A Web client is the requesting program associated with the user. The Web browser in your computer is a client that requests HTML files from Web servers.

SGML: SGML (Standard Generalized Markup Language) is a standard for how to specify a document markup language or tag set. Such a specification is itself a document type definition (DTD). SGML is not in itself a document language, but a description of how to specify one. It is a metalanguage.
SGML is based on the idea that documents have structural and other semantic elements that can be described without reference to how such elements should be displayed. The actual display of such a document may vary, depending on the output medium and style preferences. Some advantages of documents based on SGML are:
They can be created by thinking in terms of document structure rather than appearance characteristics (which may change over time).
They will be more portable because an SGML compiler can interpret any document by reference to its document tag definition (DTD).
Documents originally intended for the print medium can easily be re-adapted for other media, such as the computer display screen.
The language that this Web browser uses, Hypertext Markup Language (HTML), is an example of an SGML-based language. There is a document type definition for HTML (and reading the HTML specification is effectively reading an expanded version of the document type definition).
SGML is based somewhat on earlier generalized markup languages developed at IBM, including General Markup Language (GML) and ISIL.

SHAREWARE: Shareware is software that is distributed free on a trial basis with the understanding that the user may need or want to pay for it later. Some software developers offer a shareware version of their program with a built-in expiration date (after 30 days, the user can no longer get access to the program). Other shareware (sometimes called liteware) is offered with certain capabilities disabled as an enticement to buy the complete version of the program.
Freeware is programming that is offered at no cost. However, it is copyrighted so that you cant incorporate its programming into anything you may be developing. The least restrictive "no-cost" programs are open to copy programs in the public domain. These include a number of small UNIX programs. When reusing public domain software in your own programs, its good to know the history of the program so that you can be sure it really is in the public domain.

SIGNATURE: The automatic addition of a few lines at the foot of an E-mail. These usually consist of the sender's E-mail address, full name and other details.

SLIP: SLIP is a TCP/IP protocol used for communication between two machines that are previously configured for communication with each other. For example, your Internet server provider may provide you with a SLIP connection so that the providers server can respond to your requests, pass them on to the Internet, and forward your requested Internet responses back to you. Your dial-up connection to the server is typically on a slower serial line rather than on the parallel or multiplex lines such as a T-1 line of the network you are hooking up to.
A better service is provided by the Point-to-Point Protocol (PPP).

SMDS: SMDS (Switched Multimegabit Data Service) is a public, packet-switched service aimed at enterprises that need to exchange large amounts of data with other enterprises over the wide-area network on a nonconstant or "bursty" basis. SMDS provides an architecture for this kind of data exchange and a set of services. In general, SMDS extends the performance and efficiencies of a companys local area network (LANs) over a wide area on a switched, as-needed basis.
SMDS is connectionless, meaning that there is no need to set up a connection through the network before sending data. This provides bandwidth on demand for the "bursty" data transmission typically found on LANs.
SMDS packets contain up to 7168 bytes of data, which is large enough to accept the most common LAN packets. Each packet includes the source address and the destination address and is sent separately from other packets.
Each enterprise using SMDS is assigned from one to sixteen unique SMDS addresses, depending on needs. An address is a ten digit number that looks like an ordinary telephone number.
SMDS also provides for broadcasting packets to multiple SMDS addresses. Each SMDS company is assigned one or more group addresses that can be used to define destination groups. Group addressing is similar to LAN multicasting. It lets routing protocols, such as TCP/IP, use dynamic address resolution and routing updates.
Since SMDS is a public service, any SMDS customer can exchange data with any other customer. The SMDS Interest Group, an association of service providers, equipment manufacturers, and users, develops technical specifications, promotes awareness of SMDS, stimulates new applications, and ensures worldwide service interoperability, working with its international affiliates. Their home page provides a list of companies providing SMDS services.

SME: Small-to-medium enterprise is a convenient term for segmenting businesses and other organizations that are somewhere between the "small office-home office" (SOHO) size and the larger enterprise. The European Union has defined an SME as a legally independent company with no more than 500 employees.

SMS: SMS (Short Message Service) is a service for sending messages of up to 160 characters to mobile phones that use Global System for Mobile (GSM) communication. GSM and SMS service is primarily available in Europe. SMS is similar to paging. However, SMS messages do not require the mobile phone to be active and within range and will be held for a number of days until the phone is active and within range. SMS messages are transmitted within the same cell or to anyone with roaming capability. They can also be sent to digital phones from a Web site equipped with PC Link or from one digital phone to another. Typical uses of SMS include:
Notifying a mobile phone owner of a voicemail message
Notifying a salesperson of an inquiry and contact to call
Notifying a doctor of a patient with an emergency problem
Notifying a service person of the time and place of their next call
Notifying a driver of the address of the next pickup
An SMS gateway is a Web site that lets you enter an SMS message to someone within the cell served by that gateway or that acts as an international gateway for users with roaming capability.

SMTP: SMTP (Simple Mail Transfer Protocol) is a TCP/IP protocol used in sending and receiving e-mail. However, since its limited in its ability to queue messages at the receiving end, its usually used with one of two other protocols, POP3 or IMAP, that let the user save messages in a server mailbox and download them periodically from the server. In other words, users typically use a program that uses SMTP for sending e-mail and either POP3 or IMAP for receiving messages that have been received for them at their local server. Most mail programs such as Eudora let you specify both an SMTP server and a POP server. On UNIX-based systems, sendmail is the most widely-used SMTP server for e-mail. A commercial package, Sendmail, includes a POP3 server and also comes in a version for Windows NT.
SMTP usually is implemented to operate over TCP port 25. The details of SMTP are in RFC 821 of the Internet Engineering Task Force (IETF). An alternative to SMTP that is widely used in Europe is X.400.

SNAIL MAIL: Snail mail is a slang term for the regular postal service (for example, the Royal Mail) with the implication that it is a lot slower than e-mail. Its worth noting, perhaps, that in the early days of the Internet, it was proposed that the (then) U. S. Post Office manage e-mail. Electronic messages would come to your local post office and then be delivered to you along with the regular mail. The proposal was not considered for very long.
Snail mail or not, one must acknowledge that regular postal services offer a number of valuable services not likely to be available soon on the World Wide Web.
Write a letter. Buy a stamp, put stamp on letter. Walk to the postbox and post letter. Wait a day or two and hopefully it will have reached its intended destination...thats s n a i l - m a i l.

SNMP: Simple Network Management Protocol -- A set of standards for communication with devices connected to a TCP/IP network. Examples of these devices include routers, hubs, and switches.
A device is said to be "SNMP compatible" if it can be monitored and/or controlled using SNMP messages. SNMP messages are known as "PDU's" - Protocol Data Units.
Devices that are SNMP compatible contain SNMP "agent" software to receive, send, and act upon SNMP messages.
Software for managing devices via SNMP are available for every kind of commonly used computer and are often bundled along with the device they are designed to manage. Some SNMP software is designed to handle a wide variety of devices.

SPAM (SPAMMING): Spam is unsolicited e-mail on the Internet. From the senders point-of-view, its a form of bulk mail, often to a list culled from subscribers to a Usenet discussion group or obtained by companies that specialize in creating e-mail distribution lists. To the receiver, it usually seems like junk e-mail. In general, its not considered good netiquette to send spam. Its generally equivalent to unsolicited phone marketing calls except that the user pays for part of the message since everyone shares the cost of maintaining the Internet.
Some apparently unsolicited e-mail is, in fact, e-mail people agreed to receive when they registered with a site and checked a box agreeing to receive postings about particular products or interests. Its also possible that some spam occasionally does find a welcome audience.
A first-hand report indicates that the term is derived from a famous Monty Python sketch ("Well, we have Spam, tomato & Spam, egg & Spam, Egg, bacon & Spam...") that was current when spam first began arriving on the Internet. Spam is a trademarked Hormel meat product that was well-known in the U.S. Armed Forces during World War II.

SPIDER: A spider is a program that visits Web sites and reads their pages and other information in order to create entries for a search engine index. The major search engines on the Web all have such a program, which is also known as a "crawler" or a "bot." Spiders are typically programmed to visit sites that have been submitted by their owners as new or updated. Entire sites or specific pages can be selectively visited and indexed. Spiders are called spiders because they usually visit many sites in parallel at the same time, their "legs" spanning a large area of the "web." Spiders can crawl through a site's pages in several ways. One way is to follow all the hypertext links in each page until all the pages have been read.
The spider for the AltaVista search engine and its Web site is called Scooter. Scooter adheres to the rules of politeness for Web spiders that are specified in the Standard for Robot Exclusion (SRE). It asks each server which files should be excluded from being indexed. It does not (or can not) go through firewalls. And it uses a special algorithm for waiting between successive server requests so that it doesn't affect response time for other users.

SQL: SQL (Structured Query Language) is a standard interactive and programming language for getting information from and updating a database. Although SQL is both an ANSI and an ISO standard, many database products support SQL with proprietary extensions to the standard language. Queries take the form of a command language that lets you select, insert, update, find out the location of data, and so forth. There is also a programming interface.

SSL: SSL (Secure Sockets Layer) is a program layer created by Netscape for managing the security of message transmissions in a network. Netscapes idea is that the programming for keeping your messages confidential ought to be contained in a program layer between an application (such as your Web browser or HTTP) and the Internets TCP/IP layers. The "sockets" part of the term refers to the sockets method of passing data back and forth between a client and a server program in a network or between program layers in the same computer. Netscapes SSL uses the public-and-private key encryption system from RSA, which also includes the use of a digital certificate.
SSL is an integral part of each Netscape browser. If a Web site is on a Netscape server, SSL can be enabled and specific Web pages can be identified as requiring SSL access. Other servers can be enabled by using Netscapes SSLRef program library which can be downloaded for non-commercial use or licensed for commercial use.
Netscape has offered SSL as a proposed standard protocol to the World Wide Web Consortium (W3C) and the Internet Engineering Task Force (IETF) as a standard security approach for Web browsers and servers.

Static IP: Each computer on the Internet has an address, an example of such is 194.69.121.3 The IP address distinguishes between each and every computer on the Internet. This IP address usually changes every time you make an Internet connection, so if you come offline and then connect a little later your IP address will have changed.
You would need a Static IP Address if you wish to turn your computer into some sort of server. If you have decided to store downloadable documents or software on your server a Static IP is the solution.

SUBSCRIBE: To become of a member of. One can subscribe to a mailing list, a newsgroup, an online service or an Internet Service.

SURFING: To surf the Internet is to explore cyberspace without a predefined agenda. By cyberspace, we generally mean the World Wide Web. Prior to 1997, many people surfed gopherspace and some also surfed "FTP-space."
Note that Web users often find themselves surfing after starting out with a specific Web site to visit. The Web is like that because it is a web of interconnections whose relevance and attraction for any given Web user are impossible to predict in advance.

SWITCH: In telecommunications, a switch is a network device that selects a path or circuit for sending a unit of data to its next destination. A switch may also include the function of the router, a device or program that can determine the route and specifically what adjacent network point the data should be sent to. In general, a switch is a simpler and faster mechanism than a router, which requires knowledge about the network and how to determine the route.
On larger networks, the trip from one switch point to another in the network is called a hop. The time a switch takes to figure out where to forward a data unit is called its latency. The price paid for having the flexibility that switches provide in a network is this latency. Switches are found at the backbone and gateway levels of a network where one network connects with another and at the subnetwork level where data is being forwarded close to its destination or origin.
A switch is not always required in a network. Many local area networks (LANs) are organized as rings or buses in which all destinations inspect each message and read only those intended for that destination.

SYSOP: A sysop is the person who runs a computer server. The term is used mainly in the world of bulletin board services (BBSs) . In general, a sysop or system operator is one who runs the day-to-day operation of a server and the term suggests a person who is available when the system is. A related term is administrator. In larger computer systems, the administrator manages security and user access while a system operator monitors and performs routine operations at the computer. In smaller computer systems (for example, UNIX systems), the administrator and the system operator tend to be the same person.