How to turn off sleep

When your watching a video, DVD, you tube video or something else like that do you get annoyed when your Mac goes to sleep and you have to keep clicking the mouse or swiping the keypad every couple of minutes to stop your Mac going to sleep?  There is a way to stop it.  Go into the system preferences, go into the energy saver section, there you will see two sliders.  Drag both of them to "never" at the end.  Now your Mac will never go to sleep unless you change that setting or you order it to go to sleep or shut the lid (if you have a laptop).