A desktop cooling fan is a small air cooling device designed to help dissipate heat from computers and related equipment to enhance their performance and longevity. It usually consists of a small blowing mechanism with a fan mounted inside the unit that pulls air from the device's heat sink and blows it to the external environment, thereby lowering the temperature of the device.

Desktop cooling fans vary in design and features depending on the make and model. Some common desktop cooling fans have the following features:

1. small size: desktop cooling fans are usually small enough to be placed on a desktop without taking up too much space.

2. Multi-speed adjustment: Some desktop cooling fans have multi-speed adjustment function, you can choose different air speed and air volume to meet different cooling needs.

3. Silent design: some desktop cooling fans adopt silent design, low noise during operation, which will not affect your work and study.

4. Adjustable angle: Some desktop cooling fans have adjustable fan heads to suit different cooling needs.

5. Multi-functional design: Some desktop cooling fans also have other functions, such as connecting to a USB port to charge devices, or can be used as a small air purifier.

All in all, desktop cooling fans are a practical device that can help keep your computer and related devices at the right temperature range, thus improving their performance and lifespan.