The spider genus Steatoda, in the family Theridiidae, includes about 120 recognized species, distributed around the world (including many cosmopolitan species which are found among human populations worldwide). One common name is cupboard spider, for many species build their webs in dark, sheltered, undisturbed places around the house or garden, in sheds and garages, under garden furniture, compost bins, and the like. Signs of the cupboard spider include small white spots of spider droppings, like small splashes of paint, on the floor underneath the web. Many spiders of the genus Steatoda are often mistaken for widow spiders (Latrodectus), and are known as false widows. They are closely related (in the family Theridiidae) but Steatoda are significantly less harmful to humans. Not all Steatoda species resemble black widows – they come in many different colors and sizes, mostly smaller than Latrodectus species. Steatoda paykulliana can grow larger than the black widow, and Steatoda castanea looks more like a brown widow. Like other theridiids, they often feed on other spiders that get tangled up in their webs. Steatoda grossa sometimes preys on black widows.

The colour can range from sandy pale brown to reddish plum to satiny black. Like most spiders, its cephalothorax is smaller than its abdomen, which is somewhat egg-shaped, and can have white or beige to orange markings. Although sometimes not or partially visible, these markings usually consists of a frontal crescent, often with a dorsal line or triangular shapes or both. Orange to reddish-marked Steatoda paykulliana can be mistaken for the redback spider). In common with other members of the family Theridiidae, Steatoda construct a tangled web, i.e., an irregular tangle of sticky silken fibers. As with other web-weavers, these spiders have very poor eyesight and depend mostly on vibrations reaching them through their webs to orient themselves to prey or to warn them of larger animals that could injure or kill them.

Steatoda is known to prey on other spiders (including true black widows), crickets, ladybugs, cockroaches, and woodlice.

Some members of this genus do have bites which are medically significant in humans (such as S. grossa and S. nobilis); however, bites by Steatoda species generally do not have any long-lasting effects. There may be blistering at the site of the bite, and a general malaise lasting for several days. Symptoms can include moderate to severe pain increasing for the first hour (without severe sweating). Some people have reported mild to moderate nausea, headache, and lethargy. The duration of all symptoms and effects can range from 1 to 60 hours. The symptoms associated with the bite of several Steatoda species are known in the medical profession as steatodism; and have been described as a less-severe form of latrodectism (the symptoms associated with a widow spider bite). The redback spider antivenom has been thought to be effective at treating bites from S. grossa, after it was mistakenly administered to a S. grossa bite victim who was erroneously believed to have been bitten by the far more dangerous redback. (While the redback antivenom appears clinically active against arachnidism caused by Steatoda spiders;[68][100][101][102], as these cases are often mild and the evidence of its effectiveness is limited, this treatment is not recommended.)[90] They are not aggressive, and most injuries to humans are due to defensive bites delivered when a spider gets unintentionally squeezed or pinched somehow. It is possible that some bites result when a spider mistakes a finger thrust into its web for its normal prey, but ordinarily intrusion by any large creature will cause these spiders to flee.