When should i use a local Script and When do I use a regular Script?

I dont know when to use a "specific" script at what time.can someone help me?

You should always use local scripts for tasks related to user input, including everything related to mouse or keyboard input as well as user interfaces and camera manipulation. Tasks directly dependent on user input (including actions performed by tools in result to user input) should also be done with local scripts. For everything else, scripts that run on the server should be used. The server and the clients can communicate using the RemoteFunction and RemoteEvent objects.