Hedgehogs are small insectivores, looking much like an upside-down oval bowl, that is covered with sharp quills.  Their spines or quills have no barbs on them, and feel similar to a stiff brush. Soft fur covers their faces and bellies.

Neither legs nor tail are very visible during normal movement.   When threatened, hedgehogs roll into a ball of  interlocking spines, leaving themselves all but invulnerable to any natural predator.

Some hedgehogs have what appears to be a narrow reverse Mohawk hairdo--a narrow furrow that runs lengthwise-- which helps the quills point forward without getting crossed when bristled.  This furrow, however, is not present in all species (e.g., the Egyptian hedgehog doesn't have this).

The African Pygmy hedgehog adult ranges in weight from 250 to 600 grams, and the European species ranges from 800 to 1100 grams (there are 454 grams in a pound).

Life expectancy averages 3 to 4 years in the wild, but in captivity animals can live for up to 10 years.

The rectal temperature of hedgehogs tends to be lower than most other mammals-- about 92 degrees F. Hibernation usually occurs when the environmental temperature falls below 60 degrees F. Hedgehogs do not need to hibernate and will not do so if kept warm and well fed.

African Pygmy hedgehogs range in size from approximately 4 to 9 inches, or 10 to 22 cm.
These hedgehogs are a combination of the Algerian (Atelerix algirus) and the White-bellied (A.
albiventris).

Hedgehogs vary in color from brown to almost black with short, white and brown grooved spines over the entire dorsum of their body.

As color research has progressed, one of the things that has come to light is that there is no such thing as a ‘basic’ hedgehog color. Each hedgehog is a specific color, even though many of the gray or brown ticked ones will look ‘similar’ to the average observer.

Some of the more dramatic appearing color variations are the ‘snowflakes.’  These are often all white, or almost all white, but do not possess the albino gene. Albino hedgehogs also exist, and apparently the early problems with them being unhealthy and not terribly robust, are now largely a thing of the past.

African Pigmy hedgehogs that are available as pets, throughout North America, and most of the world, are generally a blend of a couple of species of hedgehogs: four-toed or White-bellied hedgehogs (Atelerix albiventris) and Algerian hedgehogs (A. algirus), though there has been some speculation that that there is some Pruner's (Cape) hedgehog (A. frontalis / A. pruneri) added as well.

Four-toed or White-bellied, and Algerian hedgehogs tend to have a whitish or light colored face, while Pruner's hedgehogs have a darker or masked face. The real difference, though is in the number of toes on the hind feet: Pruner's and Algerian hedgehogs have five like most hedgehogs, while the White-bellied hedgehog is also known as the Four-toed hedgehog for obvious reasons (but only the hind feet).

Egyptian or long eared hedgehogs (the ears being the most obvious differentiating factor) are,
however, known for having a somewhat more aggressive personality, and will frequently nip or
bite.

Unfortunately, there are some locations that do not yet allow pet hedgehogs.  At the moment,
hedgehogs are not permitted in (U.S. states) Alabama, California, Georgia, Hawaii and Utah.
Because some states have rather strict requirements, it is recommended you check with your own state regulations concerning the keeping of hedgehogs before acquiring one as a pet.

Canada, U.K., Europe, and Asia, too, have different requirements concerning hedgehog
ownership, so check your local laws before considering a hedgehog for a pet.