Unless you are purposefully filming a scene in one take, you are most likely going to be filming a scene more than once, with different shots to get a nice selection to edit with. This can be daunting when you come to the day of the shoot because if you're just starting out you'll probably be throwing shots out off the top of your head. "Errr...close up this time!"
"Right, what next?"
"Let's do another close up on him and then lets go wide..."
"The whole scene?"
"No I just want the ending wide"
You do the takes, get back to the edit and realise that he says the wrong line in one of the close up takes. Okay, lets have a look at the other take. Oh wait...the other take is on the other actor but you need this guys reaction. You haven't got it. Okay, at least we have a wide...oh. Only the ending.
There is a very basic strategy to follow to make sure you get a few nice takes of your scene that means you are always 'covered,' as it were.
1. Master shot - a nice large wide of the whole scene, beginning to end. This gives you something to cut to should you find a massive flaw in the close up takes and it also shows the audience where everything is happening
2. Medium - If it's a dialogue you might have both actors in shot for this or partial of one
3. Close up - The whole scene but with a close up on both actors while they talk and respond so you get reaction shots here as well
I would say, get these 3, then do whatever other strange and wonderful shot you had planned because sometimes (often in my case) your strange and wonderful shot doesn't actually give the performance what it needs and you'll find a commonplace boring shot gives the story a lot more. It's infuriating when you have too few shots to work with and even less that are great!