A portable two-way radio is a hand-held radio that can both transmit and receive (a transceiver), unlike a broadcast receiver which only receives content. Portable radios come in UHF, VHF, HF and Low Band. 800 MHZ is usually a public safety band. A push-to-talk or "Press To Transmit" (PTT) button is often present to activate the transmitter. Additionally, Hand-held radios are often called walkie-talkies or handie-talkies. Portable Two Way Radios also fit in your hand.
Portable two-way Radios are differentiated from Mobile Radios in that they have a battery (power source), and antenna system built in to the casing of the radio. 800 MHz Portable Two-Way Radios are available from 806 MHz - 870 MHz radio frequencies.