How do I determine and invest in something which can turn on in the coming years.Like a person who invested in Bitcoin in 2009(when Bitcoin was less known and popular) had received a huge appreciation in coming years.How to sense and identify that Next Big thing?

What is the collateral behind Bitcoin?Like in case of Fixed deposits Money deposited acts as a collateral.In case of a car loan Car acts as a collateral.Likewise what is collateral behind Bitcoin? BTCBTC

[Looking at the decentralized nature of crypto-currencies,Wonder if govt bans Bitcoins in future??Is it possible let's say by blocking all sites which relate to Bitcoin wallets/payments etc over the internet.In that case what would happen to our existing coins held in those wallets??]

Looking at the decentralized nature of crypto-currencies,Wonder if govt bans Bitcoins in future??Is it possible let's say by blocking all sites which relate to Bitcoin wallets/payments etc over the internet.In that case what would happen to our existing coins held in those wallets??