Ionosphere is the outermost layer of the Earth's atmosphere,extending from 60 km to 1,000 km altitude.
It mainly consists of ionized gases by the solar radiation.
It is very important layer to Earth because it influences the radio propagation to distant places on Earth.
Being ionized it reflects high frequency(shortwave) radio waves to the sky as well as to the Earth by a technique called "skip" or "skywave" propagation for the communication over long distances.
