Neo is usually dubbed as the Ethereum of China and it seems to have a strong backing in the market. It has a big potential because of its current partnerships with several big companies and its led by a strong team.
Gas is basically generated by storing NEO, and a very small sum of Gas is generated per processed block of NEO. Gas is used to control the NEO network. Companies who wish to run apps on the NEO system needs to spend Gas. The Gas spent is recycled back to the holders of NEO and also to newly generated