Advantages of running scripts locally

What are the advantages of running scripts (generally speaking) locally on a personal computer?

Is it possible to run php files locally?

I can't really say what the advantages are, as it totally depends on what you're doing.

But yes, it's possible to run locally. You just need to set up a server. Some popular ones include xampp and easyphp.

It's difficult to say advantages. Advantages as compared to what? The advantages of running any script or program are that it accomplishes a goal it was designed for to facilitate the life of the user (hopefully). Running one on your local computer is not any different than running one remotely, per se.

As for running php files locally, yes, you can do this very easily. Just install php and there you go. If you are running a linux machine, it's very easy to install and run php scripts as executables to do whatever you want them to do. If you want to run the php scripts through something like mod_php, you must install a server. Apache is small and easy to install. I'm sure there are countless others.

The main advantage is that, in the development & testing phases, if you run the scripts locally, you suffer less lag than running them on a remote server, and you don't have to upload them each time you change them, which in development phases happens very often (ie continuously).