How to select loop

can someone of you tell me how to select loop ?. I mean, for example, if I add circle with 32 vertices and extrude it, how I can select all the vertices in one part. (Circle has 64 vertices, and I want to select 32 of them by one click, without using B key). Thanks for answers.

to select an edge loop hold down the ‘alt’ key and right-click on an edge. To select a face loop you must be in face-select mode, then hold down the ‘alt’ key and click on an edge between two faces

Thanks Morio, I already knew, but I wan’t able to do it because of my window manager (GNOME). So now I’m using Shift + Alt + egde which gives me a multiple edge loop option. Thanks for answers. Problem solved.