A B C D E F G H I J K L M N O P Q R S T U V W X Y Z.

(J,K)

JAVA: Java is a programming language expressly designed for use in the distributed environment of the Internet. It was designed to have the "look and feel" of the C++ language, but it is simpler to use than C++ and enforces a completely object-oriented view of programming. Java can be used to create complete applications that may run on a single computer or be distributed among servers and clients in a network. It can also be used to build small application modules or applets for use as part of a Web page. Applets make it possible for a Web page user to interact with the page. The major characteristics of Java are: The programs you create are portable in a network. Your program is compiled into Java bytecode that can be run anywhere in a network on a server or client that has a Java virtual machine. The Java virtual machine interprets the bytecode into code that will run on the real computer hardware. This means that individual computer platform differences such as instruction lengths can be recognized and accommodated locally just as the program is being executed. Platform-specific versions of your program are no longer needed. The code is "robust," here meaning that, unlike programs written in C++ and perhaps some other languages, the Java objects can contain no references to data external to themselves or other known objects. This ensures that an instruction cannot contain the address of data storage in another application or in the operating system itself, either of which would cause the program and perhaps the operating system itself to terminate or "crash." The Java virtual machine makes a number of checks on each object to ensure integrity. Java is object-oriented, which means that, among other characteristics, similar objects can take advantage of being part of the same class and inherit common code. Objects are thought of as "nouns" that a user might relate to rather than the traditional procedural "verbs." A method can be thought of as one of the objects capabilities or behaviors. In addition to being executed at the client rather than the server, a Java applet has other characteristics designed to make it run fast. Relative to C++, Java is easier to learn. (However, it is not a language you will pick up in an evening!) Java was introduced by Sun Microsystems in 1995 and instantly created a new sense of the interactive possibilities of the Web. Both of the major Web browsers include a Java virtual machine. Almost all major operating system developers (IBM, Microsoft, and others) have added Java compilers as part of their product offerings. The Java virtual machine includes an optional just-in-time (JIT) compiler that dynamically compiles bytecode into executable code as an alternative to interpreting one bytecode instruction at a time. In many cases, the dynamic JIT compilation is faster than the virtual machine interpretation. JavaScript should not be confused with Java. JavaScript, which originated at Netscape, is interpreted at a higher level, is easier to learn than Java, but lacks some of the portability of Java and the speed of bytecode. Because Java applets will run on almost any operating system without requiring recompilation and because Java has no operating system-unique extensions or variations, Java is generally regarded as the most strategic language in which to develop applications for the Web. (However, JavaScript can be useful for very small applications that run on the Web client or server.)

JDK: Java Development Kit -- A software development package from Sun Microsystems that implements the basic set of tools needed to write, test and debug Java applications and applets See Also: Applet , Java.

JPEG: A JPEG (pronounced JAY-peg) is a graphic image created by choosing from a range of compression qualities (actually, from one of a suite of compression algorithms). When you create a JPEG or convert an image from another format to a JPEG, you are asked to specify the quality of image you want. Since the highest quality results in the largest file, you can make a trade-off between image quality and file size. Formally, the JPEG file format is ISO standard 10918. The JPEG scheme includes 29 distinct coding processes although a JPEG implementer may not use them all. Along with the Graphic Interchange Format (GIF) file, the JPEG is a file type supported by the World Wide Web protocol, usually with the file suffix of ".jpg". You can create a progressive JPEG that is similar to an interlaced GIF.

K-FLEX: Rockwell Corporation

KERMIT: Kermit is a popular file transfer and management protocol and suite of communications software programs with advantages over existing Internet protocols such as FTP and Telnet. It is freeware, developed and maintained by members of the Kermit Project at Columbia University. (However, you are invited to purchase shrink-wrapped versions and/or the manuals to help support the project.) The Kermit protocol is described as "fast, robust, extensible, tunable, and medium-independent." In addition to the protocol support, the Kermit suite includes terminal emulation, character-set translation, and scripting. The suite can be installed on almost any operating system, including Windows, UNIX, DOS, VMS, OS/2, and a number of mainframe operating systems. Most versions support both direct or dialled serial connections (with a modem) and network connections (Telnet and often others such as Rlogin, LAT, or X.25). Some advantages of Kermit are: You can write a script that will allow a sequence of file transfers to happen with a single command You can transfer an entire file directory and its subdirectories with a single command Text and binary files can be sent in the same file transfer Character-sets can be translated as part of the transfer (for example, from EBCDIC to ASCII) Files can be transferred through firewall and network address translators

KERNEL: The kernel is the essential center of a computer operating system, the core that provides basic services for all other parts of the operating system. A synonym is nucleus. A kernel can be contrasted with a shell, the outermost part of an operating system that interacts with user commands. Kernel and shell are terms used more frequently in UNIX and some other operating systems than in IBM mainframe systems. Typically, a kernel (or any comparable center of an operating system) includes an interrupt handler that handles all requests or completed I/O operations that compete for the kernel's services, a scheduler that determines which programs share the kernel's processing time in what order, and a supervisor that actually gives use of the computer to each process when it is scheduled. A kernel may also include a manager of the operating system's address spaces in memory or storage, sharing these among all components and other users of the kernel's services. A kernel's services are requested by other parts of the operating system or by applications through a specified set of program interfaces sometimes known as system calls. Because the code that makes up the kernel is needed continuously, it is usually loaded into computer storage in an area that is protected so that it will not be overlaid with other less frequently used parts of the operating system. The kernel is not to be confused with the Basic Input/Output System (BIOS). Some kernels have been developed independently for use in any operating system that wants to use it. A well-known example is the Mach kernel, developed at Carnegie-Mellon University, and currently used in a version of the Linux operating system for Apple's PowerMac computers.

KILOBYTE: As a measure of computer memory or storage, a kilobyte (KB or Kbyte*) is approximately a thousand bytes (actually, 2 to the 10th power, or decimal 1,024 bytes).