Live templates (also known as snippets in other editors) allow you to insert frequently used code constructs into your code with ease.
Simply type the abbreviation then press Tab to expand it into the full code construct. Templates can contain one or more variables or placeholders to insert code into, keep pressing Tab to move the cursor to the next variable/placeholder.
Press Cmd/Ctrl+J to view the Insert Live Template popup dialog which lists all the available live templates for the language of the current file. The dialog can also be invoked through the Code | Insert Live Template… menu item.