Decentralisation
Being a decentralised platform, blockchains are more resistant to attacks and censorship. Distributed systems remove single point of failure, which is a drawback of centralised solutions.
Freedom
On blockchain, everybody can create their own applications, without limits or permissions. Idea and creativity is all what it takes.
Ethereum
Ethereum is nowadays the most used platform for decentralised applications. It offers its own programming language, which brings it endless flexibility.