A grid of parallel lines is carved in the middle of a thick glass microscope slide that serves as the hemocytometer. It is feasible to count the number of cells in a particular volume of solution thanks to the grid's predetermined dimensions, which allow for the knowledge of the area covered by the lines. The most popular hemocytometer type includes a "H" shape etched in the centre that encloses two distinct mirror-like polished grid surfaces and serves as the location for fastening the coverslip.