Coinbase is an exchange, used by many cryptocurrency traders. This tutorial covers the three most reputable coins. See other posts about trading
There are many different ways to secure a blockchain. Some cryptocurrencies have a proof of work consensus, where extensive calculations are needed (mining), to secure the blockchain. With proof of stake, the amount of coins, residing on an online wallet have value to be selected more frequently to confirm transactions.
Pinkcoin is a proof of stake cryptocurrency. This means, that the wallet software secures the network. This is done by leaving funds in the wallet, and keep it on line. See more in the video.
Smart contracts were first released on Ethereum network. Other cryptocurrency networks, copied the smart contract functionality. So, it is important for the cryptocurrency user, to know about them.