What is LAN?
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LANs are typically high speed networks that connect computers, printers and other network devices together.
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What is Latency?
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This is the amount of time it takes a packet of data to move across a network connection. When a packet is being sent, there is "latent" time, when the computer that sent the packet waits for confirmation that the packet has been received. Latency and bandwidth are the two factors that determine your network connection speed.
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What is LCD?
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Stands for "Liquid Crystal Display." LCDs are super-thin displays that are used in laptop computer screens and flat panel monitors. Smaller LCDs are used in handheld TVs, PDAs, and portable video game devices. The image on an LCD screen is created by sandwiching an electrically reactive substance between two electrodes. This color of this substance can be changed by increasing or reducing the electrical current. Since LCD screens are based on the principle of blocking light (rather than emitting it), they use up much less power than standard CRT (Cathode-Ray Tube) monitors.
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What is LDAP?
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Stands for "Lightweight Directory Access Protocol." If you want to make directory information available over the Internet, this is the way to do it. LDAP is a streamlined version of an earlier directory standard called X.500. What makes LDAP so useful is that it works great over TCP/IP networks (unlike X.500), so information can be accessed through LDAP by anyone with an Internet connection. It is also an open protocol, which means directories can be stored on any type of machine (i.e. Windows 2000, Red Hat Linux, Mac OS X).
To give you an idea of how an LDAP directory is organized, here are the different levels of a simple LDAP tree hierarchy:
The root directory
Countries
Organizations
Divisions, departments, etc.
Individuals
Individual resources, such as files and printers.
Most LDAP connectivity is done behind the scenes, so the typical user probably won't notice it when surfing the Web. However, it is a good technology to know about. If nothing else, it is another term to impress your parents with.
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What is Leaderboard?
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As the average computer screen size has grown larger, the size of online advertisements as grown as well. The leaderboard ad, which was introduced in 2003, has a standard size of 728 pixels wide by 90 pixels tall (728x90). Compare this to its predecessor, the banner ad, which is 468 pixels wide by 60 pixels tall (468x60).
Leaderboards can contain text, images, or even animations. When a visitor clicks on a leaderboard, he or she is directed to the advertiser's website. While leaderboards are larger than the original banner ads, most Web developers have found ways to incorporate the ads in ways that are not too distracting to the user.
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What is Leaf?
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What does a computer's hard disk have in common with a tall oak? While it may not look like a tree on the outside, the hard disk is organized the same way. Directories of files and folders on a hard drive are organized into branches, where each directory is a branch with files and folders. Folders make up the branches, while files are the leaves. Therefore a leaf is a file within a directory on your hard drive.
Technically speaking, a leaf is a node on a tree with no child nodes. Because files cannot have child nodes like folders can, they are always leafs. When referring to a tree structure, a leaf can also be called a leaf node.
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What is Link?
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When you are browsing the Web and you see a highlighted and underlined word or phrase on a page, there is a good chance you are looking at a link. By clicking on a link, you can "jump" to a new Web page or a completely different Web site. While text links are typically blue and underlined, they can be any color and don't have to be underlined. Images can also serve as links to other Web pages. When you move the cursor over a link in a Web page, the arrow will turn into a little hand, letting you know that it is a link. The term "hypertext" comes from the way links can quickly send you to another Web destination.
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What is Link Farm?
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Link farm is a large group of web pages created that contain hyperlinks to one another or a specific other page. Link farms are normally created by programs, rather than by human beings.
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What is Link Popularity?
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Link popularity is a measure of the quantity and quality of other web sites that link to a specific site on the World Wide Web. It is an example of the move by search engines towards off-the-page-criteria to determine quality content. In theory, off-the-page-criteria adds the aspect of impartiality to search engine rankings.
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What is Linux?
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Pronounced "lihnuks," this is a Unix-based operating system created by Linus Torvalds. His reason for developing it was that he wasn't happy with the currently available options in Unix. So he did what anybody else would do, and created his own operating system. He freely distributed his OS, which helped it gain popularity. Today, Linux is used by hundreds of thousands of people around the world. Computer hobbyists (a.k.a. geeks) love it because it is very customizable and you can actually add your own code to the operating system. Linux is also the OS of choice for many Web hosting companies because it is far cheaper to set up and maintain than a Windows-based server. The current supported hardware platforms for Linux software are Intel, PowerPC, DEC Alpha, Sun Sparc, and Motorola.
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What is Listserv?
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This term looks like it's missing an "e", but that's how it's spelled. A listserv, or list server, is a small program that automatically sends messages to multiple e-mail addresses on a mailing list. When someone subscribes to a mailing list, the listserv will automatically add the address and distribute future e-mail messages to that address along with all the others on the list. When someone unsubscribes, the listserv simply removes the address. At least that is the way it supposed to work. Unfortunately, with some SPAM lists, unsubscribing only adds you to more lists.
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What is Localhost?
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"Localhost" refers to the local computer that a program is running on. For example, if you are running a Web browser on your computer, your computer is considered to be the "localhost." While this does not need to be specified when using a single computer, the localhost does need to be defined when running programs from multiple computers. For example, a network administrator might use his local machine to start a Web server on one system and use a remote access program on another. These programs would run from computers other than the localhost.
In the example above, the two non-local computers must be defined by their IP addresses. The local machine is defined as "localhost," which gives it an IP address of 127.0.0.1. This is considered a "loopback" address because the information sent to it is routed back to the local machine. Localhost is often used in Web scripting languages like PHP and ASP when defining what server the code should run from or where a database is located.
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What is Logic Gate?
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Logic gates perform basic logical functions and are the are the fundamental building blocks of digital integrated circuits. Most logic gates take an input of two binary values, and output a single value of a 1 or 0. Some circuits may have only a few logic gates, while others, such as microprocessors, may have millions of them. There are seven different types of logic gates.
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What is Login?
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If you are ever asked to enter your username and password, you are being asked to enter your login information. A login is a combination of information that authenticates your identity. This could be a name and password or an ID number and security code. Many secure Web sites use login information to authenticate visitors before allowing them access to certain areas of the site. Unlike the words "brush" and "comb," this term should not be used as both a noun and a verb. It should only be used as a noun, (you don't login to a server, you log in to it).
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What is Lossless?
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Lossless compression reduces a file's size with no loss of quality. This seemingly magical method of reducing file sizes can be applied to both image and audio files. While JPEGs and MP3s use lossy compression, newer compression algorithms, such as JPEG 2000 and Apple Lossless compression, can be used to create lossless compressed files.
Lossless compression basically rewrites the data of the original file in a more efficient way. However, because no quality is lost, the resulting files are typically much larger than image and audio files compressed with lossy compression. For example, a file compressed using lossy compression may be one tenth the size of the original, while lossless compression is unlikely to produce a file smaller than half of the original size.
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What is Lossy?
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Lossy file compression results in lost data and quality from the original version. Lossy compression is typically associated with image files, such as JPEGs, but can also be used for audio files, like MP3s or AAC files. The "lossyness" of an image file may show up as jagged edges or pixelated areas. In audio files, the lossyness may produce a watery sound or reduce the dynamic range of the audio.
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What is LPI?
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Stands for "Lines Per Inch." LPI is used to measure the resolution of images printed in halftones. Because halftone images are printed as a series of dots, the higher the LPI number, the more dense the dots can be, resulting in a finer resolution.
Newspapers are typically printed in a resolution of 85 lpi, while magazines may use 133 lpi or higher. Because the naked eye can distinguish halftone dots up to about 120 lpi, you are more likely to notice the dots in newspaper print than in magazines. Of course, if you look closely enough, you may be able to see the dots in images printed in 150 lpi or more. But, in normal viewing, it is natural to see the dots as a continuous image even at 85 lpi.
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