EF 50mm f/1.8 II
This lens is the first fixed lens that I have. This lens is very cheap, only about 2800 NTD (New Taiwan Dollar) or $100. This lens doesn’t have USM (ultra sonic motor), so it produce a little bit noisy when you want to take a picture. Built quality is like plastic, looked like a ‘toy’, never allow it to be fallen or it will be broken. Image quality is better than EF 18-55mm f/3.5-5.6 USM, it also has wider aperture until 1.8. Using wide aperture, you can make the background become blur. Not only that, it also help you to take a picture in low light conditions, because when you use wide aperture you can get faster shutter speed. For beginner photographer, I think this is the lens that everyone should have. Only for $100 I think it’s very reasonable, you’ve got what you paid.
More detail can be seen here: http://www.the-digital-picture.com/Reviews/Canon-EF-50mm-f-1.8-II-Lens-Review.aspx