Press releases can often trigger increased interest in a certain topic, and if a Web site link is provided in the release, this can translate to increased hits to the Web site. If the increase in traffic is so dramatic that it causes the server to be completely unreachable, the server is said to have been “slashdotted.” The name came into being after October, 1998, when a press release was published on the Slashdot.org Web site, resulting in a major surge in traffic to another Web server, causing it to go down. You can also use the term as a verb, as in, “Dude, thanks to that stupid article, our server got slashdotted today, man!”
Shareware is software that you can use on a trial basis before paying for it. Unlike freeware, shareware often has limited functionality or may only be used for a limited time before requiring payment and registration. Once you pay for a shareware program, the program is fully functional and the time limit is removed.
In the 1980s and 1990s, shareware was a popular way for small developers to distribute software. The advent of CDs allowed multiple developers to deliver their software programs as a collection, such as “Top 100 Mac Games.” Other shareware collections included utilities, graphics programs, and productivity applications. In many cases, these programs were fully functional and simply requested a donation from users. Programs that incessantly reminded users to register and pay for the software became known as “nagware.”
Today, the most common type of shareware programs are trial programs, which are also called “trialware” or “demoware.” These programs are provided as demos that you can try for a limited time, such as two weeks or one month. Once the trial period expires, you must pay for the software in order to continue using it. Most shareware demos can be downloaded directly from the software publisher’s website.
A server is a computer that provides data to other computers. It may serve data to systems on a local area network (LAN) or a wide area network (WAN) over the Internet.
Many types of servers exist, including web servers, mail servers, and file servers. Each type runs software specific to the purpose of the server. For example, a Web server may run Apache HTTP Server or Microsoft IIS, which both provide access to websites over the Internet. A mail server may run a program like Exim or iMail, which provides SMTP services for sending and receiving email. A file server might use Samba or the operating system’s built-in file sharing services to share files over a network.
While server software is specific to the type of server, the hardware is not as important. In fact, a regular desktop computers can be turned into a server by adding the appropriate software. For example, a computer connected to a home network can be designated as a file server, print server, or both.
While any computer can be configured as a server, most large businesses use rack-mountable hardware designed specifically for server functionality. These systems, often 1U in size, take up minimal space and often have useful features such as LED status lights and hot-swappable hard drive bays. Multiple rack-mountable servers can be placed in a single rack and often share the same monitor and input devices. Most servers are accessed remotely using remote access software, so input devices are often not even necessary.
While servers can run on different types of computers, it is important that the hardware is sufficient to support the demands of the server. For instance, a web server that runs lots of web scripts in real-time should have a fast processor and enough RAM to handle the “load” without slowing down. A file server should have one or more fast hard drives or SSDs that can read and write data quickly. Regardless of the type of server, a fast network connection is critical, since all data flows through that connection.
Google, Excite, Lycos, AltaVista, Infoseek, and Yahoo are all search engines. They index millions of sites on the Web, so that Web surfers like you and me can easily find Web sites with the information we want. By creating indexes, or large databases of Web sites (based on titles, keywords, and the text in the pages), search engines can locate relevant Web sites when users enter search terms or phrases. When you are looking for something using a search engine, it is a good idea to use words like AND, OR, and NOT to specify your search. Using these boolean operators, you can usually get a list of more relevant sites.
Stands for “Synchronous Dynamic Random Access Memory.” Yeah, it’s a mouthful, but if you memorize it, you can really impress your friends. SDRAM is an improvement to standard DRAM because it retrieves data alternately between two sets of memory. This eliminates the delay caused when one bank of memory addresses is shut down while another is prepared for reading.
It is called “Synchronous” DRAM because the memory is synchronized with the clock speed that the computer’s CPU bus speed is optimized for. The faster the bus speed, the faster the SDRAM can be. SDRAM speed is measured in Megahertz, which makes it easy to compare the processor’s bus speed to the speed of the memory.
Small Computer System Interface,” and is pronounced “scuzzy.” SCSI is a computer interface used primarily for high-speed hard drives. This is because SCSI can support faster data transfer rates than the commonly used IDE storage interface. SCSI also supports daisy-chaining devices, which means several SCSI hard drives can be connected to single a SCSI interface, with little to no decrease in performance.
The different types of SCSI interfaces are listed below:
SCSI-1: Uses an 8-bit bus, supports data transfer speeds of 4 MBps.
SCSI-2: Uses a 50-pin connector instead of a 25-pin connector, and supports multiple devices. It is one of the most commonly used SCSI standards. Data transfer speeds are typically around 5 MBps.
Wide SCSI: Uses a wider cable (168 cable lines to 68 pins) to support 16-bit data transfers.
Fast SCSI: Uses an 8-bit bus, but doubles the clock rate to support data transfer speeds of 10 MBps.
Fast Wide SCSI: Uses a 16-bit bus and supports data transfer speeds of 20 MBps.
Ultra SCSI: Uses an 8-bit bus, supports data rates of 20 MBps.
SCSI-3: Uses a 16-bit bus, supports data rates of 40 MBps. Also called Ultra Wide SCSI.
Ultra2 SCSI: Uses an 8-bit bus, supports data transfer speeds of 40 MBps.
Wide Ultra2 SCSI: Uses a 16-bit bus, supports data transfer speeds of 80 MBps.
Ultra3 SCSI: Uses a 16-bit bus, supports data transfer rates of 160 MBps. Also known as Ultra-160.
Ultra-320 SCSI: Uses a 16-bit bus, supports data transfer speeds of 320 MBps.
Ultra-640 SCSI: Uses a 16-bit bus, supports data transfer speeds of 640 MBps.
While SCSI is still used for some high-performance equipment, newer interfaces have largely replaced SCSI in certain applications. For example, Firewire and USB 2.0 have become commonly used for connecting external hard drives. Serial ATA, or SATA, is now used as a fast interface for internal hard drives.
Stands for “Rich Text Format.” RTF is a file format standardized by Microsoft for creating formatted text files. Unlike a basic text file, an RTF file can include information such as text style, size, and color. The nice thing about the RTF format is that it is a universal format, meaning it can be read by nearly all word processors.
This is a hardware device that routes data (hence the name) from a local area network (LAN) to another network connection. A router acts like a coin sorting machine, allowing only authorized machines to connect to other computer systems. Most routers also keep log files about the local network activity.
Stands for “Read-Only Memory.” Please do not confuse this term with RAM or a hard drive, as many people already do. ROM is memory containing hardwired instructions that the computer uses when it boots up, before the system software loads. In PCs, the instructions are read from a small program in the ROM, called the BIOS (Basic Input/Output System).
Stands for “Reduced Instruction Set Computing,”and is pronounced “risk.” It is arguably the fastest and most effiecient microprocessor technology available today. The RISC architechture is an improvement upon the CISC (Complex Instruction Set Computing) architecture used in the original Intel Pentium chips. In 1974, John Cocke of IBM Research was working on making a faster version of the CISC chip and came up with a design that significantly reduced the number of instructions need for performing computations. The new design was not only faster than the CISC architecture, but the chips were also smaller and less expensive to manufacture. Motorola’s PowerPC chips (such as the G4 in Power Macs) are the most widely used RISC-based chips. Intel has slowly been integrating RISC technology into its chips, but they still are mostly CISC-based.