It is also known as unbounded otherwise wireless transmission media. It doesn’t require any physical medium to transmit electromagnetic signals. The main features of this media are less secure, the signal can be transmitted through air, and applicable for large distances.

Radiowaves

These waves are very easy to produce as well as penetrate through buildings. In this, the transmitting & receiving antennas no need to align. The frequency range of these waves ranges from 2.4 GHz to 5GHz.