How do you input things in Android.

I want to have a simple button so when you click on it , it loads up a level select menu .

But I don’t know what the class is for touch input .

Heres the code
function Update () {

if(WHAT DO I PUT HERE) {
Application.LoadLevel("optionSelect");
}

}

What would I put so when i touch the object it’s applied to it runs ??

Look here: Unity 3d - Android, iOS, and web game development tutorials - YouTube