Name Description
Impedance The resistance and reactance of a conductor or component measured in ohms. The lower the ohm value, the better the quality of the conductor.
Inbox: An inbox is the main folder that your incoming mail gets stored in. Whether you check your mail through a webmail interface or use a program like Outlook or Mac OS X Mail, each downloaded message gets stored in your inbox.
Inkjet: Inkjet printers are the most common type of consumer printers. The inkjet technology works by spraying very fine drops of ink on a sheet of paper. These droplets are "ionized" which allows them to be directed by magnetic plates in the ink's path. As the paper is fed through the printer, the print head moves back and forth, spraying thousands of these small droplets on the page.
Install: Most software programs require that you first install them on your computer before using them. For example, if you buy Microsoft Office, you need to install it on your computer before you can run any of the included programs such as Word or Excel. You can install software from a CD or DVD, an external hard drive, or from a networked computer. You can also install a program or software update from a file downloaded from the Internet.

Installing a software program writes the necessary data for running the program on your hard drive. Often the installer program will decompress the data included with the installer immediately before writing the information to your hard drive. Software updates, which are typically downloaded from the Internet, work the same way. When you run the update, the installer file decompresses the data and then updates the correct program or operating system.
Installer: In order to install new software on your computer, you often need to run an installer program. This program unpacks compressed data included with the installer and writes new information to your hard drive. While some installers do not use compressed data, most use some level of compression since it reduces the size of the files included with the installer. This is especially helpful when downloading programs or software updates from the Internet.
Interlaced Scan: Interlaced scan refers to a video image that is displayed on a screen by scanning or displaying each line (or row of pixels) that make up the image, in an alternate order. In other words, the image lines (or pixel rows) are scanned down the screen from top to bottom, in an alternate order (lines or rows 1, 3, 5, etc... followed by lines or rows 2, 4, 6). The entire image is displayed every 30th of a second.
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. IP addresses consist of four sets of numbers from 0 to 255, separated by three dots. For example "66.72.98.236" or "216.239.115.148". 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 every time you log on). ISPs typically assign dial-up 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 or broadband connection, it is more likely that you have a static IP address.
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. IP addresses consist of four sets of numbers from 0 to 255, separated by three dots. For example "66.72.98.236" or "216.239.115.148". 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 every time you log on). ISPs typically assign dial-up 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 or broadband connection, it is more likely that you have a static IP address.
IPv4: IPv4 is the fourth revision of the Internet Protocol and is the most common version used today. It uses 32-bit addresses, which are formatted as "111.111.111.111." Each section may contain a number from 0 to 255, which provides a total of 4,294,967,296 (2^32) possible addresses.
IPv6 Pv6, also called IPng (or IP Next Generation), is the next planned version of the IP address system. (IPv5 was an experimental version used primarily for streaming data.) While IPv4 uses 32-bit addresses, IPv6 uses 128-bit addresses, which increases the number of possible addresses by an exponential amount. For example, IPv4 allows 4,294,967,296 addresses to be used (2^32). IPv6 allows for over 340,000,000,000,000,000,000,000,000,000,000,000,000 IP addresses. That should be enough to last awhile.
\n
\nBecause IPv6 allows for substantially more IP addresses than IPv4, the addresses themselves are more complex. They are typically written in this format:
\n
\nhhhh:hhhh:hhhh:hhhh:hhhh:hhhh:hhhh:hhhh

\nEach "hhhh" section consists of a four-digit hexadecimal number, which means each digit can be from 0 to 9 and from A to F. An example IPv6 address may look like this:
 
F704:0000:0000:0000:3458:79A2:D08B:4320
 
Because IPv6 addresses are so complex, the new system also adds extra security to computers connected to the Internet. Since there are so may IP address possibilities, it is nearly impossible to guess the IP address of another computer. While most computer systems today support IPv6, the new Internet protocol has yet to be fully implemented. During this transitional process, computers are often assigned both an IPv4 and an IPv6 address. By 2008, the U.S. government has mandated that all government systems use IPv6 addresses, which should help move the transition along.
ISO: An international standard published by the International Organization for Standardization. In the field of photography, the term ISO is used as a shorthand name for the standard defined by the specification for determining the sensitivity to light of film or a digital camera sensor. In film, a higher ISO number means the film is more sensitive to light. Digital camera sensors really only have one sensitivity to light though. Changing the ISO on a digital camera changes the gain in the camera, seemingly changing the sensitivity.
ISP: Stands for "Internet Service Provider." In order to connect to the Internet, you need an ISP. If you use a dial-up modem to connect to your ISP, a point-to-point protocol (PPP) connection is established with another modem on the ISP's end. That modem connects to one of the ISP's routers, which routes you to the Internet "backbone." From there, you can access information from anywhere around the world. DSL and cable modems work the same way, except after you connect the first time, you are always connected.