A wave is simply something vibrating or oscillating. Water waves are when the surface of a body of water moves up and down, seismic waves are when the earth vibrates, sound waves are when the air...
Radiowaves meduim- elecromagnetic feilds soundwaves medium- matterspeed of sound in air- 330m/sspeed of light in vaccum- 3*10^8 m/sradiowaves- transversesoundwaves- longitudanal