What are the major political parties, and how do they differ?

One of the differences between democrats and republicans lies in their views towards social issues. The Republicans tend to be conservative on social issues. They tend to oppose gay marriage and promote marriage being between a man and a woman. They also oppose abortion and promote the right of gun ownership
 Democrats tend to be more progressive in their views, favoring abortion and gay marriage, but are strongly for strict gun control laws that limit ownership..