J2EE (Java 2 Platform, Enterprise Edition)
A Sun Microsystems platform specification and branding initiative that provides a unifying umbrella for enterprise-oriented Java technologies. J2EE focuses on server-side, multitier services. J2EE includes the Java Server Pages, Java Servlets and Enterprise JavaBeans programming models, a number of protocols and application programming interfaces, a reference implementation, a test suite, and an application model.

J2ME (Java 2 Platform, Micro Edition)
An edition of Sun's Java platform that focuses on small-form-factor devices, such as personal digital assistants, pagers and cell phones.

J2SE (Java 2 Platform, Standard Edition)
The basic Java platform, directed at desktop users.

JAD (joint application development)
An application development process aimed at achieving high levels of functional quality through the participation of prospective end users. It is especially effective in developing user interface requirements.

JAR (Java Archive)
A platform-neutral Java file format for downloading multiple applets from the Internet in a single transaction. Although originally intended for applets, JAR files may also include applications and components. JAR files incorporate file compression and allow authors to digitally sign individual entries. See Java.

Java
The term "Java" can be applied to Sun Microsystems' Java platform or to its Java programming language. The Java platform include the Java Virtual Machine (JVM), which provides a uniform Java byte code emulator for Java's cross-platform runtime environment; the Java programming language, which provides a robust, object-oriented language for constructing Java components and applications; and the standard Java class library packages, which provide sets of reusable services that promote consistency among components and applications. The Java programming language is based on C and extends and complements the basic capabilities of Hypertext Markup Language. Java permits the creation of applications and application modules (called "applets") that run in the JVM on the browser.

Java applet
A small piece of Java code that implements a specific function. Applets may run on a server or be downloaded and run on the client's machine.

JavaBeans
Similar to Microsoft's ActiveX, this Sun Microsystems' technology enables external applications access each other's services.

Java Card
A set of Java application programming interfaces for smart cards.

JavaScript
A scripting language targeted specifically to the Internet. It is the first scripting language to fully conform to ECMAScript, the Web's only standard scripting language. Despite its name, JavaScript is not a derivative of Java; its origin is Netscape's Livescript language. JavaScript is, in fact, closer to C/C++ in syntax than it is to Java.

Java servlet
A Java program that operates in conjunction with a Web server, and can output Hypertext Markup Language to a browser or even communicate with Java applets. Servlets offer an alternative to using Common Gateway Interface and server application programming interfaces to communicate with Web server processes.

JAXM (Java API for XML Messaging)
An application programming interface (API) from Sun Microsystems. JAXM is used to build Java-based e-commerce applications that can generate and exchange Extensible Markup Language (XML) messages.

JAXP (Java API for XML Processing)
A Sun Microsystems application programming interface (API) that enables Extensible Markup Language (XML) documents to be read, manipulated and generated in Java-based applications.

JBIG (Joint Bitonal Image Group)
An standard for black-and-white and gray-scale image compression.

JCAHO (Joint Commission on Accreditation of Healthcare Organizations)
An U.S. independent, not-for-profit organization devoted to healthcare standards setting and accreditation.

JCL (Job Control Language)
A language used to communicate with IBM's Multiple Virtual Storage (MVS) operating system. JCL is used to tell the system who a user is, what programs are being invoked and what resources will be needed. See MVS.

JCP (Java Community Process)
A program created by Sun Microsystems to provide an open forum for Java developers, licensees and other members. JCP's charter is to develop Java technology specifications, reference implementations and technology compatibility kits.

JDBC (Java Database Connectivity)
A standard that provides connectivity between Sun Microsystems' Java platform and a range of database management systems. JDBC provides a call-level application programming interface for database access based on Structured Query Language.

JDK (Java Development Kit)
A Sun Microsystems product that provides the underlying technologies for implementing the Java programming language.

JES (Job Entry Subsystem)
The component of IBM's Multiple Virtual Storage (MVS) operating system that reads in jobs, interprets their Job Control Language (JCL) and schedules their execution. See JCL and MVS.

Jini
A distributed-computing product introduced by Sun Microsystems in 1998. The system enables any devices that use Sun's Java programming language to communicate and work with one another.

JIT (just in time)
The concept of reducing inventories by working closely with suppliers to coordinate delivery of materials just before their use in the manufacturing process.

JITT (just-in-time training)
A training methodology in which users are trained in a technology just when they begin using it.

jitter
A slight movement of a transmission signal in time or phase, which can introduce errors and loss of synchronization for high-speed, synchronous communications. See phase jitter.

JMS (Java Messaging Service)
Part of Sun Microsystems' Java 2 Platform, Enterprise Edition (J2EE), JMS is an application programming interface that connects Java programs to messaging middleware, such as IBM's MQSeries and Tibco Software's Rendezvous. See J2EE.

JNDI (Java Naming and Directory Interface)
A specification from Sun Microsystems that allows Java applications to store and retrieve named Java objects. It also provides methods for performing standard directory operations such as searching for objects using their attributes.

JNI (Java Native Interface)
An application programming interface developed by Sun Microsystems that defines a standardized way of naming and calling native functions created in a non-Java language. With JNI, the Java Virtual Machine (JVM) can locate and invoke native methods, or those native methods can perform Java-specific functions such as creating Java objects or calling Java methods. See JVM.

JOLAP (Java Interface for OLAP)
A Java application programming interface for the Java 2 Platform, Enterprise Edition (J2EE) environment. JOLAP supports the creation and maintenance of online analytical processing (OLAP) data and metadata, independent of vendor. See OLAP.

JPEG (Joint Photographic Experts Group)
A standard for still-image compression.

JSP (Java Server Pages)
A mechanism that allows Java source code to be embedded into Hypertext Markup Language (HTML) files. This source code is executed on the Web server (by servlets), and the resulting HTML is output to a Web browser. JSP allows many types of developers to interact with both HTML and Java in designing the interface to Java applications.

JSR (Java Specification Request)
The formal document submitted to propose the development of a new specification — or a major revision to an established specification — under the Java Community Process (JCP). See JCP.

JSR 168 (Java Specification Request 168)
A specification from the Java Community Process (JCP) organization designed to enable interoperability between portals and "portlets." It defines a set of application programming interfaces for portal computing, addressing areas such as aggregation, personalization, presentation and security. See JCP and portlet.

JTAPI (Java Telephony Application Programming Interface)
An application programming interface for developing Java-based telephony applications.

jukebox
An automatic media handler for an optical disk drive, also called a library. An optical jukebox is designed to move optical platters in and out of optical drives. The intent is to provide a large amount of easily accessed storage in a "near-line" fashion. Jukeboxes use robotics. Similar in concept to music jukeboxes, the robot arm locates the appropriate disk and, if it is not already mounted in a drive, clears the drive and loads the selected disk.

JVM (Java Virtual Machine)
The virtual machine (VM) that runs in the Java environment. See VM and Java.