We can measure Angles in Degrees.
There are 360 degrees in one Full Rotation (one
(Angles can also be measured in Radians)
(Note: "Degrees" can also mean Temperature, but here we are talking about Angles)
The Degree Symbol: °
We use a little circle ° following the number to mean degrees.
For example 90° means 90 degrees
This is how large 1 Degree is
The Full Circle
A Full Circle is 360°
Half a circle is 180°
Quarter of a circle is 90°
Why 360 degrees? Probably because old calendars (such as the Persian Calendar) used 360 days for a year - when they watched the stars they saw them revolve around the North Star one degree per day.
Measuring DegreesWe often measure degrees using a protractor:
The normal protractor measures 0° to 180°
You can also get full-circle protractors.
But they are not as commonly used because they are a bit big and don't do anything special.