why we need Java

Answer 1

In simple words we need Java to develop application softwares such as BookMyShow, Amazon, Flipkart etc.., which in turn interacts with system software i.e operating system ( even interpreter , compilers etc..)
Java doesn't interact or communicate with system ( hardware) directly...!!! instead it comunicates with the outer environment such as results obtained by the interaction with hardware therefore even Java s called as intermediate language.

Answer 2

you can do everything with java. java is used to create Web applications and platforms. It was designed for flexibility, allowing developers to write code that would run on any machine, regardless of architecture or platform.