What is an expression?

An expression is a combination of variables, constants, operators and functions that is evaluated to another value. An expression is not an instruction. It does not do anything.

Example 1

2 + 5 is an expression. It evaluates to an integer value 7.

Example 2

5 % 2 is an expression. It evaluates to an integer value 1.

Example 3

"Hello" + "World" is an expression. It evaluates to a string value HelloWorld.

Example 4

4.5 - 0.5 is an expression. It evaluates to a float value 4.0.