Most computers use High-resolution monitors. They are anywhere from 620 lines to 1080 lines. The normal TV is low-resolution from the 1940's and has only 480 lines. Even if you could connect it, it wold look fuzzy.
If you have a high-def TV, it may have HDMI inputs, DVI inputs or mini-DVI inputs. If so, and your computer has one of these outputs, you can connect it with no problems if you can find the right cable.