There are many different types of triangles, let's go find some.

An acute triangle is a triangle with all three angles acute, meaning less than ninety degrees.

An obtuse triangle is one with one obtuse angle, meaning it is greater than ninety degrees, and two acute angles. Since a triangle's angles must add up to one-hundred and eighty degrees, no triangle can have more than one obtuse angle.

Acute and obtuse triangles are the two different types of oblique triangles, triangles that are not right triangles because they have no ninety degree angles.

A right triangle is a triangle in which one angle is a right angle, or exactly ninety degrees and the other two angles acute.