what is a roofing square

https://star-wiki.win/index.php/How_to_Measure_a_Roof:_A_Practical_Guide_for_Accurate_Estimates

A roofing square is simply a 10-foot by 10-foot area of roof surface, used by contractors to estimate materials and costs. Think of it as a unit of measurement, not a physical square you can hold. For example, a 2,000-square-foot roof has 20 squares. Knowing this helps you understand quotes and plan your roofing project.