Qi is only the latest and greatest in the technology industry. It aims to standardize wireless charging across all devices. Meaning, no matter the device type, if it has wireless charging built in, it should power that device.
How does this work? Glad you asked! It works by using both magnetic induction and magnetic resonance to transmit energy, similarly to how the Earth has a magnetic field surrounding it. Wireless charging devices contain a coil that converts this magnetic energy into electrical energy, which then charges the battery.