The sand cat (Felis margarita), also known as the sand dune cat, is the only felid found primarily in true desert, and has a wide but apparently disjunct distribution through the deserts of northern Africa and southwest and central Asia. Since 2002 this small cat has been listed as Near Threatened by IUCN due to concern over potential low population size and decline.

The sand cat lives in arid areas that are too hot and dry even for the African Wildcat: the Sahara, the Arabian Desert, and the deserts of Iran and Pakistan.

Victor Loche was the first European who described the sand cat in 1858. He named the species Felis margarita after Jean Auguste Margueritte, the leader of the expedition during which he had encountered the animal.

The sand cat is a relatively small, stocky cat with short legs, a long tail, and large, pointed ears. They range from 39 to 57 centimetres (15 to 22 in) in length, plus a 23 to 31 centimetres (9.1 to 12 in) tail, and weigh from 1.4 to 3.4 kilograms (3.1 to 7.5 lb). The head is conspicuously broad, and the ears are so widely spaced that they can be flattened horizontally, or even pointed down to aid in hunting.

Sand is a naturally occurring granular material composed of finely divided rock and mineral particles. The composition of sand is highly variable, depending on the local rock sources and conditions, but the most common constituent of sand in inland continental settings and non-tropical coastal settings is silica (silicon dioxide, or SiO₂), usually in the form of quartz.

The second most common form of sand is calcium carbonate, for example aragonite, which has mostly been created, over the past half billion years, by various forms of life like coral and shellfish. It is, for example, the primary form of sand apparent in areas where reefs have dominated the ecosystem for millions of years, like the Caribbean.

In terms of particle size as used by geologists, sand particles range in diameter from 0.0625 mm (or ⅟16 mm) to 2 mm. An individual particle in this range size is termed a sand grain. Sand grains are between gravel (with particles ranging from 2 mm up to 64 mm) and silt (particles smaller than 0.0625 mm down to 0.004 mm). The size specification between sand and gravel has remained constant for more than a century, but particle diameters as small as 0.02 mm were considered sand under the Albert Atterberg standard in use during the early 20th century. A 1953 engineering standard published by the American Association of State Highway and Transportation Officials set the minimum sand size at 0.074 mm. A 1938 specification of the United States Department of Agriculture was 0.05 mm. Sand feels gritty when rubbed between the fingers (silt, by comparison, feels like flour).

The domestic cat (Felis catus or Felis silvestris catus, informally Felis domesticus) is a small, usually furry, domesticated, carnivorous mammal. It is often called the housecat when kept as an indoor pet, or simply the cat when there is no need to distinguish it from other felids and felines. Cats are valued by humans for companionship and ability to hunt vermin and household pests. They are primarily nocturnal.

Cats are similar in anatomy to the other felids, with strong, flexible bodies, quick reflexes, sharp retractable claws, and teeth adapted to killing small prey. As crepuscular predators, cats use their acute hearing and ability to see in near darkness to locate prey. Not only can cats hear sounds too faint for human ears, they can also hear sounds higher in frequency than humans can perceive. This is because the usual prey of cats (particularly rodents such as mice) make high frequency noises, so the hearing of the cat has evolved to pinpoint these faint high-pitched sounds. Cats also have a much better sense of smell than humans.