Blockchain technologies

Blockchain (BC) is basically a distributed database with a consensus mechanism. Depending on concept and implementation, there could be many BC technologies. Most prominent is Bitcoin, which is the first and oldest and most used. Second most interesting is Ethereum, which is still in beta, but [looks] very promising. Then goes the whole bunch of alternative blockchains, consensus algorithms, layers on top of other chains, etc. It is difficult to find your way around in the forest of these technologies and possibilities / advantages. A thought by Andreas M. Antonopoulos, a Bitcoin fanatic, seems useful:

Bitcon is based on economic logic. Therefore 'the winner takes all' logic works there. That is, it is not that 'the best technology' wins, but 'good enough' technology which gets implemented early and accumulates traction, eventually wins and is very difficult to change afterwards (think of IPv4 vs IPv6). This is why Bitcoin is not going anywhere (probably) and Ehtereum may have difficult time to take off (?).

The bottom line is that it may make more sense to look at technologies which build additional layers on Bitcoin, rather than new blockchains.