i am starting to learn Noncommutative Geometry, but I did not attend course of Algebraic Topology during studies. For next week I need to know what is principal bundle, in both senses of Cartan and Steenrod. Do You know where it is well explained?
And more generally, do You know any Algebraic Topology book which will be good for person who wants to use it as a tool (in NCG in my case), not to study it as a main domain of interest?