Hair Type

| Hair shape

The hair type depends also on the shape, which is also determined by the ethnic group, and it can be divided into:

• Cymotrichous hair: wavy or curly with an oval section, which is typical of Caucasian (European) ethnic groups
  
• Straight hair: smooth with a round section, which is typical of the Mongolian (Asian) ethnic groups
  
• Ulotrichous hair: woolly and frizzy with a flat section, which is typical of black (African) ethnic groups

| Hair color and length

The type of hair also differs depending on the color. Hair color is given by melanin. Eumelanin is present in dark (black) hair and pheomelanin in light hair (red, blond, golden).

The length varies greatly from person to person. The average length never goes beyond one meter. The hair can therefore be short, bob-cut, shoulder lenght or long.
Hair grows at an average speed of 0.3 mm per day (almost 1 cm per month), obviously this growth is not infinite and each person is more or less predisposed to reach a certain length.

| The diameter of the hair or thickness

The type of hair also varies according to its thickness. The diameter of the hair depends on the width of the germinal area of the hair. We therefore distinguish three types of hair: fine, medium, thick.

• Fine hair: it is a type of hair with little cortex. The main characteristics of this type of hair are: greater resistance to humidity, greater fragility, difficulty in maintaining styling, combing and chemical treatments
  
• Thick hair: it has a greater amount of cortex. It also shows the following characteristics: little resistance to humidity, it is more resistant, responds better to chemical treatments and holds the style
  
• Medium hair: it has an intermediate amount of cortex and therefore intermediate characteristics