Both dandruff and lice are things that take place on or near your scalp that you do not want. However, they are two very different things. Dandruff is a dry scalp. It looks like there are white things in your hair. This is because the scalp has become so dry that it has begun to crack and peel.
The white stuff that you see in your hair is the dry scalp that has peeled away. The bad thing about that is that people can usually see when you have dandruff. They rarely can know if you have lice in your hair. Lice are when you have shared a hairbrush with someone who has lice. You will have bugs and their eggs on the strands of your hair near the scalp.