Whose (something) is it?

In English, we have a lot of sentences like these: 

It’s my birthday!

It’s really nice out today.

...where “it” doesn’t have any particular meaning, but we need to use it. Asking “___ ___ is it?” is the question form for one of these sentences:

Whose birthday is it?

How nice is it outside?

We still need “it” in these sentences because the sentence needs a subject.

(someone’s) move

When we play a board game, each person usually has a small game piece, which they move according to the rules of the game. When it is someone’s turn to move their piece, we call it a “move.” 

I’m planning my next move.

Ooh, that’s a risky move.

In other situations, such as sports, business, and politics, a “move”  is an action with a goal in mind: 

That was a really bad political move.