Fans are hardware devices used for cooling other devices which generate lots of heat.
Computer fans are a type of hardware used for cooling core components. Fans come in various shapes and forms, often with specific functionality. For example, most processors have a dedicated fan to cool the CPU. Power supply units and north bridges may also have dedicated fans. General cooling fans are called case fans, as they cool an entire case rather than just a single component.
Fan speed on Ubuntu can be measured using the