What is Java?

• Java is a “high-level” computer programming language.
  
• It has a set of rules that determine how the instructions are written. These rules are known as its “syntax”.
  
• The high-level instructions are translated into numeric codes that computers can understand and execute.
  
• Java was created by a team led by James Gosling for Sun Microsystems. When Java 1.0 was released to the public in 1996, its main focus had shifted to use on the Internet. It provided more interactivity with users by giving developers a way to produce animated webpages.
• Java source code files (with a .java extension) are compiled into a format called bytecode (with a .class extension), which can then be executed by a Java interpreter. Compiled Java code can run on most computers because Java interpreters and runtime environments, known as Java Virtual Machines (JVM), exist for most operating systems, including UNIX, the Macintosh OS, and Windows. Bytecode can also be converted directly into machine language instructions by a just-in-time compiler (JIT).

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