difference between System.out.println() and System.err.println()

Question

What is the difference between System.out.println() and System.err.println() in Java?

Answer 1

System.out.println("wassup"); refers to when you have to output a certain result pertaining to the proper input given by the user whereas System.err.println("duh, that's wrong); is a reference to show that the input provided is wrong or there is some other error.

Most of the IDEs show this in red color (System.err.print).