Trivia: What does a protractor measure?
Correct Answer: Angles
So why is this answer correct? : Protractors, in use since the 13th century, are specifically used for creating and measuring plane angles. Protractors have also been used in a similar fashion to astrolabes and sextants — to observe heavenly bodies and plot the position of a ship. Nowadays, the people most likely to encounter a protractor are architects and geometry students.