Public Toilets In Different Countries

Roman toilets are commonly thought to be used in the sitting position. But sitting toilets only came into general use in the mid-19th century in the western world. The Roman toilets were probably elevated to raise them above open sewers, rather than for sitting. Squat toilets are still used by the majority of the world's population.
Sustainability
The amount of water used in toilets is a significant portion of personal water usage, with an average of 90 litres (20 imp gal; 24 US gal) used per capita per day in 1990 in the United States. One system used to combat this is the "yellow mellow" system, in which a toilet is only flushed when it contains solid waste, and not only one person's-worth of urine. The custom is often described by the phrase "If it's yellow, let it mellow. If it's brown, flush it down." This system reduces the frequency of toilet flushing significantly.