The measurement of an angle is given by the measurement of its opening. The default unit of measurement for an angle is the **degree**, whose symbol is **º**.

Taking a shallow or half-turn angle and dividing it into 180 equal parts, we determine 180 angles of the same measure. Each of these angles represents an angle of **1st degree** (1º).

To measure angles, we use an instrument called **protractor**. The protractor is already graduated with divisions from 1st to 1st. There are two types of protractor: 180º and 360º.

The degree comprises the following submultiples:

- O
**minute**stands for of degree. It is indicated**one minute**by 1 '.

- O
**second**stands for of the minute. It is indicated**one second**by 1 ".

Therefore, we can conclude that:

1º = 60'.60 = 3.600"When an angle is measured in degrees, minutes and seconds, we are using the **sexagesimal system**.