Confused about black plastic sheeting for vegetable garden

I've been dealing with a lot of weeds for the last few years in my vegetable garden, more than I can handle when it gets hot and enough to be discouraging. They pop up before vegetables I've planted manage to.

I've read that a black plastic sheet like this is good for preventing weeds. However, I'm confused about how to use it.

First of all, is this temporary? Do I place it now in the fall and remove it in the spring before planting?

Second, do I put anything over top or underneath during the winter? I have some compost — should I put that beneath the plastic? I imagine if the plastic is temporary I don't want mulch etc on top but how about underneath?