Bottled Dispensers: These use large (typically 3–5 gallon) replaceable jugs.
Top-Load: The bottle sits inverted on top, and gravity feeds the water into the system.
Bottom-Load: The bottle is hidden in a bottom cabinet, and an internal pump draws water upward.
Point-of-Use (POU) / Bottleless: These connect directly to a water line, providing an unlimited supply and often using advanced filtration to purify the water.
Countertop / Tabletop: Compact units designed to sit on counters or desks, ideal for small spaces like apartments or small offices.
Wall-Mounted: Fixed to a wall and often found in high-traffic public areas like schools or hospitals; these are frequently referred to as water fountains.