"AIO" is an abbreviation for "all-in-one," and in the context of "all-in-one" water coolers, the phrase provides a very accurate explanation of how these coolers function. Like air coolers, all-in-one (AIO) water coolers are simpler water cooling kits designed to provide a thermal solution that can be installed and then forgotten. They function according to the same fundamental idea that expensive custom water cooling systems do. For example, you install a copper or metal block on top of your CPU socket and a radiator on top or front of your computer's case. Moreover, the fans dissipate heat from the radiator, and the coolant liquid flows around the cooler with the assistance of a pump. Compared to normal coolers, AIO coolers have a few items streamlined for your convenience. There is generally no reservoir for the coolant, and you don't need to design and work on piping in the case. That's because AIO coolers arrive with soft, sleeved tubing that goes right from the reservoir to the CPU block and vice versa. That tubing is also tightly sealed and pre-filled, so you cannot put in your coolant. In the same vein, there is almost little likelihood of a coolant leak unless the tubing gets physically destroyed. Moreover, you are not supposed to put in your coolant. In addition, AIO coolers have competitive prices. For example, a dependable all-in-one (AIO) water cooler may cost anywhere from $70 to $200, depending on whether you want more quality materials or a larger radiator. This pricing compares to a custom water cooling loop, costing several hundred dollars.