.
Probably The Most Versatile Square – Here's How It's Used
The most obvious us for the speed square is to use it as a square, to drawing square layout lines, checking to see if your circular saw base is square with the blade and so on.
Another use for the speed square is as a protractor to measure and mark different angle other than 90 degrees.
You can use the square as a guide for other power tools. Most commonly used as a guide for a circular saw.
You use it to draw parallel lines down the length of a board or on sheet goods. If you've tried this with your tape measure you've probably ended up with a few slivers from time to time.
Watch the video for use #5 and great descriptions on the uses above.
.
.
Planer