i couldn’t find a video explain waht it does. So i will ask you guys
It does what it says Overwrite Clips, use to be able to move a video or sound clip over another video or sound clip. The part of the target clip that meshes with the clip being moved will be cut out.
Oh, i see! Somehow it just slip through my head , properly because my English is not my first. So I was confuse
Thanks for explaining steenbeck!