The angle which is less than 90 Degree is called as

Acute Angle: An angle which measures less than 90 Degree is called an acute angle.
Right Angle: An angle which measures exactly 90 Degree is called a right angle.
Obtuse Angle: An angle that measures greater than 90 degree and up to 180 Degree is known as the obtuse angle
Straight Angle:The angle which measures exactly 180 Degree is called a straight angle.
Reflex Angle: The angle which measures greater than 180 Degree and less than 360 Degree is known as the reflex angle.
Full Angle: The angle which measures exactly 360 Degree is called a straight angle.