Cell death can be divided in two major categories. Necrosis results from cellular injury caused by external factors such as trauma or infection. Programmed cell death is a regulated process that is mediated by various intracellular programs. Types of programmed cell death include apoptosis, anoikis, necroptosis, ferroptosis, pyroptosis, and parthanatos. These types of programmed cell death other than apoptosis have also been termed stress-induced cell death (SCID).