1.What is infura?
Infura is a set of tools to help create applications which connect to the Ethereum Blockchain
2. Why do so many people use infura?
It makes life easier for developers so they don’t have to store the whole blockchain, they can connect quickly and simply, as well as storing data with them off-chain but storing the hash of that data on-chain.
3. What are the flaws of having so many people using it?
It becomes more centralized the more people use this service and this could be shut down or censored as they are not themselves decentralized.
4. What is the alternative to using Infura?
Everyone can host their own node on the main chain, however there are trade offs as mentioned in #2.