Basic Input & Output in Programs
In the Wolfram System's standard notebook interface, you are directly giving input and getting output every time you press . Although much more rarely needed than in more primitive languages, the Wolfram Language also allows you to get input and generate output as side effects in a computation.
Print — print any expression, including graphics, as output
PrintTemporary — print temporarily, cleaning up when a computation is complete
Echo — print and return any expression
EchoEvaluation — print expressions and the results of evaluating them