Actually, there is only one race; the human race. Obviously, several different colors of people exist on the earth that have distinctive characteristics, but they are the same race. Because Scripture does not state where these differences came from, I'm not going to be dogmatic but I will tell you about the various theories.
One theory says that Adam and Eve were medium-brown, possibly because they were made from the earth. That medium-brown couple produced all the varieties of colors; they might have had 100 children or more with all the colors represented in the first family.
A second theory says that the first division of colors came when God put a mark upon Cain (Genesis 4:15) after Cain killed Abel. The Bible doesn't say what the mark is, but some have tried to say that Cain became the first black man. Of course, that theory only explains two colors and does not consider the flood bringing the human race back to one family I personally don't believe this theory either.
A third theo says that Noah cursed Canaan after Noah got drunk (Genesis 9:25). Some people think Canaan became the first black man. I don't believe this theory because I don't think any color of people are cursed and it only explains two colors. The Bible says Canaan shall be a servant of servants. Many have used this verse with their twisted logic to justify slavery.
The fourth (and I think the best) theory says the races came from the Tower of Babel. Genesis 10:20 says, "These are the sons of Ham, after their families, after their tongues, in their countries, in their nations." Perhaps all families, countries, nations, and tongues were created or developed from this event. Maybe the colors were divinely created at that time, or maybe they are just a natural product of a small group of people speaking their own language and marrying back to their own parent stock. Racial traits become more pronounced in a small inbreeding group. The Bible isn't clear on this subject. These four theories are the only ones that I know. I efer the Tower of Babel explanation. I know the Bible does say in Acts 17 that all nations are of one blood so there is no reason for anyone to be a racist.