When do you use code blocks?

Question

When do you use code blocks in C/C++/C#, etc.? I know the theoretical reason behind them, but when do you use them in real programs?

EDIT: I have ju

Answer 1

In addition to the obvious ("when required by syntax", like in a switch or a try catch finally),
Whenever you need to treat a block of 2 or more statements as an atomic unit