A colony or group of cells living in an unnatural environment (in vitro). Cell culture 1also refers the growing of cells outside the body in such a way that their population is amplified, so that scientists will have sufficient cells to study and use in various types of experiments (see cell biology).

Three main types of cell cultures are "primary cultures" (which are cells taken from chickens or humans; these cultures cannot be kept alive indefinately and eventually die out (with the exception of work done recently with cells that have not differentiated yet)), naturally surviving cells (like those taken from rodents, or unusual cells from a human fetus/embryo; these cells may under go a "crisis" in which many of the cells, will die, but an immortal strain will emerge and continues to live), and cancerous cells (from tumors, or cells that have been made cancerous after exposure to virus, drugs or other methods).

These cells are either adherent (flat little cells that generally stick to an enriched gel in a petri dish), or cells that are in suspension.

See also stem cell and cell biology.