A protractor is a device used in drafting and drawing: it's mainly used for drawing and measuring angles. Don't show up to geometry without your protractor!
In math class, you use many tools, such as a calculator. Another is the protractor, which is handy when you're studying geometry. Protractors are designed to help you measure and draw angles. You can make a rhombus or an isosceles triangle with a protractor. A protractor can help you measure existing angles too, like if you’re taking a geometry test and need to compare angle measurements. Graphic artists, architects, and other professionals who need to make angles use protractors.