Christianity vs. Catholicism

I have always had trouble distinguishing between Christianity and Catholicism. Not being religious myself, I have trouble recognizing difference between sects, even if they are the two main branches of the largest religion in the world. This website provided an overview of the different ways Catholics and Christians attain salvation and what the major differences are between these two massive sects of an already huge religion.

http://www.justforcatholics.org/a19.htm