Numbered in both 360? and 90? segments and divided in 1/2?. Cut out center for easy pick-up; packaged in a plastic pouch.A protractor is a measuring instrument for measuring angles. Most protractors measure angles in degrees (?). Most protractors are divided into 180 equal parts. They are used for a variety of mechanical and engineering-related applications, but perhaps the most common use is in geometry lessons in schools.