High altitude winds are considered to be the most favorable source of renewable energy in the future. In this paper, review has been conducted on harnessing of high altitude wind energy via floating type aero-generators. This new generation of systems employs tethered wings, aircrafts, multi-copters, balloons in order to harness the higher atmospheric winds. A number of systems based on different concepts have been analyzed and tested from mid-seventies, with a rapid acceleration in last couple of years. This paper presents a comprehensive overview of different technologies that have been designed/ built to harvest the energy of high altitude winds, highlighting the accomplished results, technological issues and classification of such systems have been proposed on the basis of their working and design. Apart from the Airborne Wind Energy or High-Altitude Wind Energy based systems, a brief overview on offshore floating wind turbines have also been provided.