What is the name of a triangle in which none of the angles are greater than 90 degrees?

A triangle in which none of the angles are greater than 90 degrees is called an "acute triangle." In an acute triangle, all three angles are less than 90 degrees, giving it a sharp appearance. This classification is distinct from right triangles, which contain one 90-degree angle, and obtuse triangles, which have one angle greater than 90 degrees.