What term is used to describe a line that extends straight up from the floor?

The term used to describe a line that extends straight up from the floor is a vertical line. In the context of hair cutting and styling, understanding the concept of vertical lines is crucial as they play a significant role in the overall shape and structure of a hairstyle. Vertical lines create a sense of length and height, and they can dramatically influence the illusion of volume and movement in the hair. When a haircut employs vertical lines, it helps in reducing bulk and adding definition, making it an essential technique for stylists to master.

In contrast, horizontal lines are those that run parallel to the floor and are often used to create width. Diagonal lines can either add movement or change the shape of the hair but do not extend straight up like vertical lines do. Curved lines introduce softness and fluidity in design but also do not fit the description provided. Understanding these different types of lines and their effects can help students achieve desired styles effectively.