You will frequently see little boxes pop up on your screen that ask you to make a decision. Decisions like OK, Save, Cancel. In almost all cases you will notice one of the little buttons with those words in them has an outline around it. That is the default button. You do not need to use your mouse if the one you are going to click on is the default one. Just press the Enter button on your keyboard – there are two of them. Saves wear and tear on the hand and is quicker too.