If you need to rip wood, then the Speed Square can be an asset as well. Because of its lipped fence you can make a straight ...

A square has four right angles (90°). Each diagonal splits a corner into two angles of 45°. Note also that the diagonals cut each other in half at right angles. A rectangle has four right angles.

You don’t always need a protractor. A right angle looks like the corner of a square or the edge of a book. It is a perfect 90°, which is often shown by a small square drawn in between the two ...