BTC: An abbreviation for "Bitcoin" and it is the first decentralised cryptocurrency to be made, and it is also the core of crypto. All altcoins revolve around this being the "station" for Bitcoin.
Bitcoin Cash, BTC Segwit and Segwit2x: All altcoins that have different size blocks, and they are supposed to overtake bitcoin.
Is there are a free air drop just like before when bitcoin cash was release? If they are supposed to overtake bitcoin, probably it is one of their strategy to give people afree air drops with new bitcoin or you can call it another altcoin so that leaving the real bitcoin. The bitcoin cash are the prove, that some miners are decide to mine bitcoin cash than bitcoin because it's more profitble. what's your thought?