All the statements that end in a semicolon (;) are expressions. A block is a statement that has a set of statements and variables inside the {} scope. The last statement of a block is the value that will be assigned to the variable. When we close the last statement with a semicolon, it returns () to the variable.

In the preceding recipe, the first statement which is a variable named x_val , is assigned to the value 5. Second, y_val is a block that performs certain operations on the variable x_val and a few more variables, which are x_squared and x_cube that contain the squared and cubic values of the variable x_val , respectively. The variables x_squared and x_cube , will be deleted soon after the scope of the block.

The block where we declare the z_val variable has a semicolon at the last statement which assigns it to the value of (), suppressing the expression. We print out all the values in the end.

We print all the declared variables values in the end.