Java is a compiled programming language commonly used to write web applets. Web applets are client-side executable programs that can be embedded into a webpage (but require a Java plug-in). However, Java applets are virtually obsolete after the invention and growing popularity Macromedia Flash.

Javascript is a client-side scripting language (enterpreted rather than compiled) whose syntax is very similar to Java. Javascripts can be included in an HTML document (webpage) to be enterpreted and executed by the broswer displaying the document (page). Unlike Java, Javascript is far from obsoletion.

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