The shape of hair follicles is the main reason why some people have curly hair while others have straight hair. Curly hair follicles are more oval-shaped than straight hair follicles. This means that the hair shaft is forced to curve as it grows out of the follicle.

There are also a number of other factors that can affect hair texture, including genetics, ethnicity, and hormones.

• Genetics: Hair texture is largely determined by genetics. If your parents have curly hair, you are more likely to have curly hair.
• Ethnicity: There is a general trend that people of African descent tend to have curlier hair than people of European descent. However, there is a lot of variation within each ethnic group.
• Hormones: Hormones can also affect hair texture. For example, pregnant women often experience changes in their hair texture, such as increased curliness.

The shape of the hair follicle is determined by the genes that we inherit from our parents. These genes code for the proteins that make up the hair follicle. If the genes code for oval-shaped hair follicles, the hair shaft will be forced to curve as it grows out of the follicle.

Other factors that can affect hair texture include the amount of moisture in the hair, the way the hair is styled, and the amount of sun exposure the hair receives.

Curly hair is often more difficult to manage than straight hair. It can be more prone to frizz and tangles. However, there are a number of products and styling techniques that can help to manage curly hair.