Whats the difference between a beat and pause in script?

A beat is supposed to describe a part in the script where the theme of the scene changes. For instance, Joe and Mary are talking about getting a cat. They discuss which color to get. They discuss who's going to take care of it. BEAT. They start talking about how unfair it is that people keep dying when it snows. While pauses are just taking a pause. BOTH beats and pauses have no business being in scripts. The playwright doesn't even originally write the beats and pauses in (most playwrights don't, anyhow.) The person who writes those into the scripts are the first production's stage managers, (they're also the ones who write in all the stage directions.) Beats, Pauses and stage directions are merely suggestions and should be ignored completely. I cross them out. Nobody's going to tell me when to pause but ME.

A beat is a short pause - a slight hesitation, a bit more than you give a comma in a sentence. Like a beat in music, but in the speaking it is a slight gap when something should occur but taking the beat brings attention to what comes next. A pause is a break, a stopping of speech or movement.