The map is a fiber bundle with fiber F if for every point there is an open neighborhood and a "fiber preserving homeomorphism" .

In particular, the projection map is the trivial fibration over X with fiber F.

What I don't understand is the following example.

Let be the unit circle with basepoint . Consider the map given by . Then is a locally trivial fibration with fiber a set of n distinct points (the nth root of unity in

What is the in this example? is it an arc? Why is the fiber F the nth root of unity here? What is this "fiber"? Is there a geometrical meaning to the here?

I do not really have any background on topology. So appreciate if someone can explain this to me. Thanks!