Statement Blocks 

• All control structures are divided into the control statement (which we will explain below) and the statement block. The statement block is simply a group of commands that are executed together. This block is grouped by enclosing the commands within curly braces ({}). For example, the following is a simple statement block. 

{
statement one
statement two
statement three
}

• Perl will execute each statement in a statement block from beginning to end as a group. When, how, or if the script will execute the commands however, is determined by the control statement. 

Additional Resources:

• Perl 
• Perl Resources 

Perl Control Structures
Table of Contents
Using the if, elsif, else and unless Control Statements