How do I lock the camera on the player's head?

I have some tips!(These must be local scripts)

Interpolate

Interpolation is a function, when ran, it can make your camera run smoothly to the destination it needs to go to:

workspace.Camera:Interpolate(workspace.Player.Head, workspace.Player.Head, 5)
--Go to the player's head and make the camera focus on the player's head; it will take 5 seconds to reach the destination.

http://wiki.roblox.com/index.php?title=Interpolate is a good place to study, like how alphawolvess said.

Hope this helps!