i have knowledge about scripting in roblox, however ive always wondered when do we use localscripts or when do we use normal scripts?
Heres some links to wiki pages..
http://wiki.roblox.com/index.php?title=API:Class/LocalScript
It's really easy.
As you may know, localscripts are local client based, and they take the Player you're controlling as "special" so it lets you do stuff such as finding the player with localplayer, and in filtering enabled, these scripts wont get replicated, unless you try to use Remote Events, so you can replicate Localscripts to the players.
Scripts are managed by the server, so it takes every player like the same person, Because it aint managed by the Clients (i assume) it wont take resources from the PC more than internet.
Im a newbie for scripting, but i assume this helped you in something.