what do the tropic of capricon, tropic of cancer lines, artic, an antartic circles represent?

2 answers

These articles have your answers.

http://en.wikipedia.org/wiki/Tropic_of_Capricorn

http://en.wikipedia.org/wiki/Arctic_Circle

Note that it's ARCTIC and ANTARCTIC.
The Tropic of Capricorn line represents the farthest south direct sunlight goes.

The Tropic of Cancer line represents the farthest north direct sunlight goes.

Those are all that I know. Hope I helped!