The hair type helps in deciding on the kind of products that are needed and the methods of hair-care that should be followed.
Normal Hair Type
If you have a normal scalp, then you can use any shampoo meant for normal hair. You do need to use a light conditioner each time you shampoo.
If you have dry hair, you need to use a more intensive conditioner meant for dry hair.
If you need to shampoo your hair more than twice a week, then you should alternate between a normal hair shampoo and a dry hair shampoo.
Dry Hair Type
With normal hair, you need to use a shampoo meant for dry hair and a regular conditioner.
With dry hair, you need to use a shampoo meant for coloured or treated hair with a similar conditioner.
Oily Hair Type
If your scalp is oily, you need to use a shampoo meant for oily hair and a lighter conditioner.
If you have dry hair, you need to use a shampoo for oily hair, with an intensive conditioner meant for dry hair.
If you need to shampoo your hair more than twice a week, then you should alternate between a shampoo meant for oily hair and one meant for normal hair.