Site logo, www.grelf.net
 

What is Java?

 

Java is a programming system (language, library and execution environment) from Oracle. It is available in several versions and for several platforms as free downloads from Oracle's Java web site. Java has existed since 1995 and is the major language for programming web servers.

Among its strengths are that

Perhaps perceived as a weakness of Java is that its source code is not fully compiled to the native code of the processor on which it is to be run. Instead it is compiled to the instruction set of an imaginary ("virtual") machine which is then interpreted immediately before execution. People worry that this results in poor performance, and so Java could not be suitable for processing massive amounts of data such as in digital images. However this is not the case, as we will demonstrate. In fact the use of intermedate "byte code", as it is called, has important benefits in the implementation of Java itself, particularly with regard to portability and security. Byte code is designed for fast interpretation and Java Virtual Machines (JVM's) are written to exploit this to the full.

 

 Some Java programming terms and abbreviations

If you would like to learn to program in Java there is a self-study course here. It assumes some programming experience. If you have never programmed before then I would strongly recommend starting with a simpler language which is readily available to anyone: JavaScript. JavaScript is not related to Java. It is just an unfortunate accident of history that they have similar names.

Next page