A hemocytometer is a specialized microscope slide used for counting and measuring the concentration of cells in a liquid sample. It consists of a thick glass slide with a grid pattern etched into its surface, allowing for precise counting of cells under a microscope. This tool is commonly used in laboratories for various applications, including blood cell counts and cell culture analysis. To use a hemocytometer, a small volume of the sample is placed in the chamber, and the cells are counted within specific grid squares. The results can then be used to calculate the total number of cells per milliliter. Hemocytometers are essential in fields like hematology, microbiology, and cell biology.