An acute angle is an angle that is an angle that is below 90 degrees.

It's a cutie!

A right angle is an angle that is an angle that is exactly 90 degrees.

It's alright in my books!

An obtuse angle is an angle that is an angle that is above 90 degrees but under 180 degrees.

It's obsotusely amazing!

A straight angle is an angle that is an angle that is exactly 180 degrees.

It's straight up cool!