There are two basic types of toilets: the dry toilet, and the wet toilet - the latter being the most commonly known and producer of blackwater. The dry toilet needs no plumbing for water input or evacuation, but is often coupled with some ventilation system.

The ancient cities of the Indus Valley Civilization, e.g., Harappa and Mohenjo-daro which are located in present day India & Pakistan had flush toilets attached to a sophisticated sewage system—and other forms of toilets were used both in the time of the Romans and Egyptians as well. Although a precursor to the modern flush toilet system was designed in 1596 by Sir John Harington, the toilet did not enter into widespread use until the late nineteenth century, when it was adopted in English upper class residences.

Nearly 40 percent of the world's population lacks access to toilets.

Types of toilets

There are also many different ways to clean oneself after using the toilet. A lot depends on national mores and local resources. The most common choice in the Western world is toilet paper, sometimes used in conjunction with the bidet. (See Toilet paper and Anal cleansing for a discussion of the many alternatives used through history and in different cultures.) In the Middle East and some countries in Asia, and South Asian countries such as India and Pakistan, the custom is to use water, either with or without toilet paper.Fact: date=May 2007 Traditionally, the left hand is used for this, for which reason that hand is considered impolite or polluted in many eastern countries.Fact: date=May 2007

The most common type of toilet in modern cities is the flush toilet, in which water takes away the waste through sewers to a waste treatment plant. In rural areas where sewers are not practical, septic tanks may be installed instead.

The most common design in first-world countries is the sitting toilet. Some other countries use the squat toilet.

Public toilets

main: Public toiletMerge: date=August 2008

A public toilet may or may not cost money to use; for those that do, see "pay toilet". Between the categories of outright free and outright pay toilets, there is a grey area of toilets where a fee is expected, but not enforced. A charge levied in the UK during the mid-20th century was one British penny, hence the generally adopted term "spend a penny" meaning to use the toilet.Fact: date=May 2007 Public facilities often have several toilets partitioned by stalls (US) or cubicles (UK). Facilities for men often also have separate urinals, either wall-mounted fixtures designed for a single user, or a constantly-draining basin or trough for collective use. Wall-mounted urinals are sometimes separated by small partitions or other obstructions for privacy, i.e., to keep the user's genitals hidden from public view.Fact: date=May 2007