iTunes Definition iTunes is an audio playback program developed by Apple Computer. You can use iTunes to import songs from CDs as well as other audio files from your hard drive. The program can also download songs (for a small fee) from the iTunes Music Store. While songs are the most common files played by iTunes, you can also play spoken word files, such as audio books or other recordings. iTunes also has a radio option that allows you to play live streams of Internet radio from a variety of s...

Encoding Definition Encoding is the process of converting data from one form to another. While "encoding" can be used as a verb, it is often used as a noun, and refers to a specific type of encoded data. There are several types of encoding, including image encoding, audio and video encoding, and character encoding. Media files are often encoded to save disk space. By encoding digital audio, video, and image files, they can be saved in a more efficient, compressed format. Encoded media files are...

Media Compression Definition Like file compression, the goal of media compression is to reduce file size and save disk space. However, media compression algorithms are specific to certain types of media, such as image, audio, and video files. Most popular image formats use some type of compression. Three of the most common include JPEG, GIF, and PNG. JPEG compression, which is commonly used for digital photos, incorporates a lossy compression algorithm that averages nearby colors and removes co...

Shell Definition Most people know of shells as small protective coverings for certain animals, such as clams, crabs, and mollusks. You may also find a shell on the outside of an egg, which I highly recommend you remove before eating. In the computer science world, however, a shell is a software program that interprets commands from the user so that the operating system can understand them and perform the appropriate functions. The shell is a command-line interface, which means it is soley text-...

Terminal Definition The word "terminal" comes from early computer systems that were used to send commands to other computers. Terminals often consist of just a keyboard and monitor, with a connection to another computer. The purpose of a terminal is not to process information (like a typical computer), but to send commands to another system. For example, a network administrator may use a terminal to log in to a network and manage devices connected to the network. With modern computers, the word...

WYSIWYG Definition Stands for "What You See Is What You Get," and is pronounced "wihzeewig." WYSIWYG refers to software that accurately represents the final output during the development phase. For example, a desktop publishing program such as Photoshop is a WYSIWYG graphics program because it can display images on the screen the same way they will look when printed on paper. Word processing programs like Microsoft Word and Apple Pages are both WYSIWYG editors, because they include page layout m...

Linux Definition Linux (pronounced "lih-nux", not "lie-nux") is a Unix-like operating system (OS) created by Linus Torvalds. He developed Linux because he wasn't happy with the currently available options in Unix and felt he could improve it. So he did what anybody else would do, and created his own operating system. When Linus finished building a working version of Linux, he freely distributed the OS, which helped it gain popularity. Today, Linux is used by millions of people around the world....

Runtime Definition Runtime is the period of time when a program is running. It begins when a program is opened (or executed) and ends with the program is quit or closed. Runtime is a technical term, used most often in software development. It is commonly seen in the context of a "runtime error," which is an error that occurs while a program is running. The term "runtime error" is used to distinguish from other types of errors, such as syntax errors and compiliation errors, which occur before a ...

JRE Definition Stands for "Java Runtime Environment" and may also be written "Java RTE." Java is a programming language, similar to C. However, since it is a newer language, it is not natively supported by all operating systems. Therefore, a Java Runtime Environment may need to be installed on your computer for Java applets and Java applications to run. The JRE, or Java RTE, is developed by Sun Microsystems (the creator of Java) and includes the Java Virtual Machine (JVM), code libraries, and ...

JVM Definition Stands for "Java Virtual Machine." A JVM is a software-based machine that runs Java programs. It can be installed on several different operating systems, including Windows, OS X, and Linux. JVMs allow Java apps to run on almost any computer. A Java virtual machine processes instructions similar to a physical processor. However, the Java code from a .JAVA file must first be converted into instructions the JVM can understand. This binary format, called "bytecode," can be processed ...