Is better proof-of-work or proof-of-stake cryptocurrency ?

What is the difference between proof-of-work or proof-of-stake cryptocurrency ? Which one is better ?

Proof of stake concept was created as an alternative to Proof of work concept. Proof of stake has its advantages and disadvantages, but in general, it is considered to be more advanced method than Proof of work. The main difference between PoS and PoW are:

• Proof of Stake - persons can mine or validate block transactions according to how many coins they have. Simply said, the more coins miner owns, the more mining power he has.
• Proof of Work - available hardware resources are important. Miners are required to have powerful hardware devices. The larger hardware resources available, the bigger chance of "winning the reward" miner has.
  

Proof of work concept has higher energy consumption. Proof of stake concept is more energy efficient. The strongest cryptocurrency Bitcoin is using PoW.