What is a blank check for?

Blank check is a check which is doesn't have a dollar amount specified but it has been signed by the owner. It can be used for all sorts of things,such as; If you want to pay something by the other hand, it means by your friend but you didn,t know what amount should you pay, you might give a blank check to the person. but remember that you have to give the check to the right person for example;your family,your sitter or someone else that you believe.