A square grid pattern places points perpendicular from one another (for aligned grids) or randomly (for unaligned grids) such that each point falls in an invisible square. The length of each grid side is dependent on the area of the sampling space. The area is then divided into N number of blocks, where N is the number of desired samples. Each block is then treated as a square and the square root of the area of a single block gives the estimated side length of the invisible grid definition.
Aligned Grid Unaligned Grid