EmperorTeddyIn short it can send and receive radio waves on wide range of frequencies (software defined radio). One of its main benefits is ability to switch frequency really fast. Its uses are many and varied. It can be used for WIFI or Bluetooth communication, HAM radios, radio telescopes, listening to radio stations, analog and digital TV channels, airplane positioning network (ADS-B), spectrum analyzer, etc. But since it's a software defined radio you need software for these functionalities. Device itself only offers interface for data.
If this is something that interests you, I really advise lower end devices as entry-point. For example RTL-SDR. Price for those is around 25$ and allows similar functionality but only up to 1.75GHz.