The warthog (Phacochoerus africanus) is a wild member of the pig family that lives in Africa. They are the only widely recognized species in their genus, though some authors divide them into two species. On that classification, P. africanus is the Common (or Northern) Warthog and P. aethiopicus is the Desert Warthog, also known as the Cape Warthog or Somali Warthog. The name comes from the large warts found on the head of the warthog, which serve the purpose of defense when males fight.

Warthogs are identifiable by the two pairs of tusks protruding from their mouth, which are used as weapons against predators. They range in size from 0.9 to 1.5 meters (2.9-4.9 feet) in length and 50 to 150 kg (110-330 pounds) in weight.

A grouping of warthogs is called a sounder. Common Warthog sounders are usually composed of 3 to 10 animals, although groups as large as 30 have been anecdotally reported. The "core" of the sounder is usually a sow with offspring. A sounder can be composed of multiple females and their respective offspring, and females tend to stay with their family group for several breeding seasons.

On the other hand, males tend to live alone or in small bachelor groups with individuals that come and go, but they tend to stay within their natal range. Mature males only join female groups when sows are in heat. Males are not territorial, but will fight among themselves for mating opportunities during breeding season, sometimes inflicting significant and serious wounds with tusks.

Although warthogs are commonly seen (and associated with) open grasslands, they will also seek shelter and forage in denser vegetation. In fact, warthogs prefer to forage in dense, moist areas when available. They eat grass, berries, bark, roots, and carrion, as well as insects and grubs. Areas with many bulbs, rhizomes and nutritious roots can support large numbers of warthogs. Warthogs are powerful diggers, using both heads and feet. Although they can dig their own burrows, they commonly occupy abandoned aardvark burrows. The warthog commonly enters burrows "back-end first", with the head always facing the opening and ready to burst out as needed.

Warthogs are very fast runners and quite capable jumpers. They will often run with their tail in the air. Despite a poor eyesight, warthogs have a good sense of smell, which they use for locating food, detecting predators and recognizing other animals.

The common warthog diet is omnivorous, composed of grasses, roots, berries and other fruits, bark, fungi, eggs, dead animals, and even small mammals, reptiles and birds. The diet is seasonably variable, depending on availability of different food items.

Although capable of fighting, and males will aggressively fight each other during mating season, their main defense is to flee by means of fast sprinting. The main warthog predators are men, lions, leopards and hyenas. Cheetahs are also capable of taking small warthogs.

Wild warthogs can live up to 15 years. Captive warthogs may live as long as 18 years. The typical gestation period is 5 or 6 months and the litter size is 2 to 8 piglets, although 2 to 4 is more typical. Piglets are weaned at 3 or 4 months of age, reaching sexual maturity at 18 to 24 months. Females may give birth twice a year.