You are bald if you have little or no hair on your head. Some men go bald as they get older, but other people shave off their hair to become bald.
The man in the picture is bald, but his dog certainly is not!
A beard is the hair that grows on the chin of an adult man or animal. Male goats have beards. The hair that grows on your toplip is called a moustache.
Dreadlocks are like ropes growing in your hair. They form when your hair matts together. Dreadlocks will form on their own if you never comb your hair, but most people encourage dreadlocks to form. Dreadlocks form more easily in people with tightly curled hair.