In terms of sides:
1) Equilateral - all sides are equal
2) Isosceles - two legs are equal
3) Scalene - no sides are equal
In terms of interior angles:
1) Equiangular - all angles are equal
2) Right - an angle is 90 degrees
3) Obtuse - an angle is more than 90 degrees
3) Acute triangle - all angles are acute (less than 90 degrees) but not equal
Any triangle may be both in terms of sides and angles:
- A triangle may be equilateral and equiangular.
- A triangle may be isosceles and right.
- A triangle may be isosceles and obtuse.