Why did the north and south fight?

The North, more formally known as the Union, wanted to abolish slavery in all of the states because they thought (and were right in doing so) that slavery was inhumane.

The South, formally known as the Confederacy, didn't think so. Granted there may have been some Confederates that treated their slaves almost like equals, they still considered them property instead of people.

I am a little fuzzy on the exact details, but I believe that is what helped contribute to the beginning of the Civil War.

One of the main reasons was because the South didn't like what the North was doing by trying to control the trade system.