On a Mac, which tutorial do i need to record a screen tutorial on youtube?

I'm trying to make a tutorial on youtube and I'm wondering which software I need to be using for a Mac to record the screen while i'm working on it.





Thanks for your help.On a Mac, which tutorial do i need to record a screen tutorial on youtube?
You could use iShowU or for a free alternative find a webcam recorder like Quicktime and use Camtwist and upload those.