Find all objects that has specific tag

I want to find all the objects that are tagged as “LightUsers”, and change their Light component’s value “light.enabled” to false… I don’t know how to find all of the objects tagged as specific tag… I think this is easy, but i don’t get the stuff with arrays and that…
I’m using C# for scripting.

find objects store them in array and get their light component

 GameObject[] objs ;
        objs = GameObject.FindGameObjectsWithTag("LightUsers");
       foreach(gameObject lightuser in objs) {
            lightuser.GetComponent<light>().enabled=false;
        }

GameObject.FindGameObjectsWithTag

You will get a List with all Objects with the provided Tag. Here some C# Code.

GameObject[] lightUsers;
lightUsers = GameObject.FindGameObjectsWithTag("LightUsers");