Angles are everywhere. They are pretty much corners but all with different measurements. No matter what shape you have, they will always have angles. The basic unit for measuring angles is degrees. Different types of angles have different amounts of degrees. For example, a rectangle has all 90 degree angles. An angle with exactly 90 degrees is called a right angle. Some triangles have right angles too, but they can only have one since two angles of a triangle will always be acute no matter what the third angle is. An acute angle is an angle with a measurement less than 90 degrees, and an obtuse angle is an angle with a measurement greater than 90 degrees but less than 180 degrees. 180 degrees is exactly half of a circle. An angle with a measurement of exactly 180 degrees is called a straight angle. Straight angles are just straight lines.