Computer & Internet Glossary Part 2

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E-mail It's hard to remember what our lives were like without e-mail. Ranking up there with the Web as one of the most useful features of the Internet, e-mail has become one of today's standard means of communication. Billions of messages are sent each year. If you're like most people these days, you probably have more than one e-mail address. After all, the more addresses you have, the more sophisticated you look... E-mail is part of the standard TCP/IP set of protocols. Sending messages is typically done by SMTP (Simple Mail Transfer Protocol) and receiving messages is handled by POP3 (Post Office Protocol 3), or IMAP (Internet Message Access Protocol). IMAP is the newer protocol, allowing you to view and sort messages on the mail server, without downloading them to your hard drive. Though e-mail was originally developed for sending simple text messages, it has become more robust in the last few years. Now, HTML-based e-mail can use the same code as Web pages to incorporate formatted text, colors, and images into the message. Also, documents can be attached to e-mail messages, allowing files to be transfered via the e-mail protocol. However, since e-mail was not originally designed to handle large file transfers, transferring large documents (over 3 MB, for example) is not allowed by most mail servers. So remember to keep your attachments small! Ethernet Just to be clear, the first syllable is pronounced like "Heath" as in Heath Bar?, not like "Beth" as in Bethany. I found this out the hard way (ridiculing laughter), but at least you don't have to. Ethernet is the most common type of connection computers use in a local area network (LAN). An Ethernet port looks much like a regular phone jack, but it is slightly wider. This port can be used to connect your computer to another computer, a local network, or an external DSL or cable modem. Two widely-used forms of Ethernet are 10BaseT and 100BaseT. In a 10BaseT Ethernet connection, data transfer speeds can reach 10 mbps (megabits per second) through a copper cable. In a 100BaseT Ethernet connection, transfer speeds can get up to 100 mbps. There is also a new technology called "Gigabit" Ethernet, where data transfer rates peak at 1000 mbps. Now that's fast. Firewall While the term "firewall" creates a powerful visual picture, in reality, it doesn't involve any fire or pyrotechnics. A computer firewall is used to protect a networked server or client machine from damage by unauthorized users. The firewall can be either hardware or software-based. A router is a good example of a hardware device that often has a built-in firewall. Software programs that monitor and restrict external access to a computer can also serve as firewalls. A network firewall allows only certain messages from the Internet to flow in and out of the network. So, I guess in a way it really is like a wall of fire. Well, sort of. Freeware Like shareware, freeware is software you can download, pass around, and distribute without any initial payment. However, the great part about freeware is that you never have to pay for it. No 30 day limit, no demo versions, no disabled features -- it's totally free. Things like minor program updates and small games are commonly distributed as freeware. Though freeware does not cost anything, it is still copyrighted, so other people can't market the software as their own. Gigabyte A gigabyte consists of roughly 1 billion bytes. To be exact, there are 1024 megabytes, or 1,073,741,824 bytes in a gigabyte, but 1 billion is a much easier number to remember. Because of the large size of today's hard disks, storage capacity is usually measured in gigabytes. Abbreviation: "GB". Hacker While this term originally referred to a clever or expert programmer, it is now more commonly used to refer to someone who can gain unauthorized access to other computers. A hacker can "hack" his or her way through the security levels of a computer system or network. This can be as simple as figuring out somebody else's password or as complex as writing a custom program to break another computer's security software. Hackers are the reason software manufacturers release periodic "security updates" to their programs. While it is unlikely that the average person will get "hacked," some large businesses and organizations receive multiple hacking attempts a day. Hard Drive This is where all the data in your computer is stored. It is where all your files and folders are physically located. A typical hard drive is only slightly larger than your hand, yet it can hold over 100 GB of data. The data is stored on a stack of disks that are mounted inside a solid encasement. These disks spin extremely fast (typically at either 5400 or 7200 RPM) so that data can be accessed immediately from anywhere on the drive. The data is stored on the hard drive magnetically, so it stays on the drive even after the power supply is turned off. The term "hard drive" is actually short for "hard disk drive." The term "hard disk" technically refers to the actual disks inside the drive. However, all three of these terms are usually seen as referring to the same thing -- the place where your data is stored. Since I use the term "hard drive" most often, that is the correct one to use. Home Page This is the starting point or front page of a Web site. This page usually has some sort of table of contents on it and often describes the purpose of the site. For example, http://www.sharpened.net/index.html is the home page of Sharpened.net. When you type in a basic URL, such as "http://www.cnet.com," you are typically directed to the home page of the Web site. Many people have a "personal home page," which is another way the term "home page" can be used. Host This is a computer that acts as a server for other computers on a network. It can be a Web server, an e-mail server, an FTP server, etc. For example, a Web host is what provides the content of Web pages to the computers that access it. A host is also known as the mother computer. Well, not really, I just made that up. HTTP Stands for "HyperText Transfer Protocol." This is the protocol used to transfer data over the World Wide Web. That's why all Web site addresses begin with "http://". Whenever you type a URL into your browser and hit Enter, your computer sends an HTTP request to the appropriate Web server. The Web server, which is designed to handle HTTP requests, then sends to you the requested HTML page. Internet Believe it or not, the Internet was created way back in 1969, during the Cold War, by the United States military. It was meant to be a "nuke-proof" communications network. Today, the Internet spreads across the globe and consists of countless networks and computers, allowing millions of people to share information. Data that travels long distances on the Internet is transferred on huge lines known collectively as the Internet backbone. The Internet is now maintained by the major Internet service providers such as MCI Worldcom, Sprint, GTE, ANS, and UUNET. Because these providers make huge amounts of revenue off the Internet, they are motivated to maintain consistent and fast connections which benefits everyday Internet users like you and me. Many people think the Internet and the World Wide Web are the same thing. They're not! The World Wide Web is what you are browsing right now. It is one of the many features of the Internet. E-mail, FTP, and Instant Messaging are also features of the Internet. IP Stands for "Internet Protocol." It provides a standard set of rules for sending and receiving data through the Internet. People often use the term "IP" when referring to an IP address, which is OK. The two terms are not necessarily synonymous, but when you ask what somebody's IP is, most people will know you are referring to their IP address. That is, most computer nerds or people who have read the Sharpened.net glossary. IP Address Also known as an "IP number" or simply an "IP," this is a code made up of numbers separated by three dots that identifies a particular computer on the Internet. Every computer, whether it be a Web server or the computer you're using right now, requires an IP address to connect to the Internet. For example, the IP address of everyone's favorite computer resource, Sharpened.net, is 209.123.247.45. The IP address of the computer I'm using right now is 66.72.98.236. Your Internet Service Provider (ISP), will assign you either a static IP address (which is always the same) or a dynamic IP address, (which changes everytime you log on). ISPs typically assign users a dynamic IP address each time they sign on because it reduces the number of IP addresses they must register. However, if you connect to the Internet through a network, it is more likely that you have a static IP address. ISPs and organizations usually apply to the InterNIC for a range of IP addresses so that all their clients have similar addresses. There are three classes of IP address sets that can be registered: Class C, which consists of 255 IP addresses, class B, which contains 65,000 IP addresses, and class A, which includes hundreds of thousands of IP addresses. Because there are so many computers now connected to the Internet, the InterNIC is actually running out of IP addresses. Therefore, Class A and Class B address blocks are very hard, if not impossible, to get. Most large companies have to register multiple Class C addresses instead. To resolve this problem, the Internet Engineering Task Force, which created the original IP address standard, is working on a new protocol called "IP Next Generation" or "IPng." ISDN Stands for "Integrated Services Digital Network." No, it's not the same thing as the ISBN you see in books. ISDN is a data transfer technology, created in 1984, that can transfer data significantly faster than a dial-up modem. ISDN enables wide-bandwidth digit