Blond or blonde is a light color of hair or a person with this color hair. The spelling blonde means a female with this hair colour, and the spelling blond may mean a male with the same hair color. The color itself can have either spelling (blonde or blond), according to Merriam-Webster's Dictionary.
Natural blonds have quite fair skins, and their skin is finer (less thick) than people with dark skin. Light skin is natural amongst people living (or whose ancestors lived) in northern climates. It is an adaptation for their skins to make vitamin D. This vitamin is essential for health, and people in northern climates may not make enough.
One thing to mention: hair colour may change during life, and many children have blond hair at first, but it grows darker as they get older. That's a normal thing. Blondes do not make the melanin for their hair (and skin) to go dark. It is very unusual to see a blond person with dark skin, but it does happen occasionally.
People who are blonde have less pigment in their hair than dark haired people. To be blonde is usually to have blonde ancestors. It is not albinism. People may also use chemicals to make themselves blonde, but that is just a fashion thing.
Natural blondes are most common around the Baltic Sea and Scandinavia. The Nordic countries such as Sweden, Norway, Denmark, Iceland, and Finland also have many blond people. Ireland and Scotland also have a high number of natural blondes. Likewise in Poland), north-western parts of Russia.