Two Basic Types of Modern Toilet
• Dry Toilet
The dry toilet needs no plumbing for water input or evacuation, but is often coupled with a ventilation system.
• Flush (wet) Toilet
The most common toilet in developed nations is the flush toilet, in which water carries the waste into sewers. It disposes human waste by using water to flush it through a drainpipe to another location. Flushing mechanisms are found more often on western toilets (used in the sitting position), but many squat toilets also are made for automated flushing. Modern toilets incorporate an 'S','U', 'J', or 'P' shaped bend that causes the water in the toilet bowl to collect and act as a seal against sewer gases. Since flush toilets are typically not designed to handle waste on site, their drain pipes must be connected to waste conveyance and waste treatment systems. Flush toilets were once called water closets in the 18th and 19th Centuries.
