What is difference between java and java script?

Answer 1

Java is a Programming Language & JavaScript a Scripting Language.
Programming languages are languages whose instructions are translated (compiled) directly into machine code. Scripting languages do not require the compilation step and are rather interpreted.

Answer 2

Java case is particular, as it's in between compiled and interpreted, called "semi-compiled", as it require to be compiled in a pseudo code to be real time interpreted: not completly compiled in direct understandable instructions for processor, as other "full" compiled languages... This is a gain of efficiency as the script is pre-analyzed and optimized, in a time outside of running time, comparing to "full" interpreted languages ^^