Hey @emjoe,

thank you for reading everything - I know, it was a lot. But I felt that anything less wouldn't be enough.

Don't worry, it takes a bit of time to grasp everything but I'll try to explain to you (in a non-technical way)

Steem works with a system called DPOS (Delegated Proof of Stake - https://bitshares.org/technology/delegated-proof-of-stake-consensus/) which is an alternative to e.g. POS (Proof of Stake) or POW (Proof of Work).

For this DPOS - you need Witnesses who are operating a Witness Server that produces blocks.

Let me quote this wiki article:

A Steem Witness is a person who operates a witness server (which produces blocks), and publishes a price feed of STEEM/USD to the network. Witnesses' computers in the Steem network have a job that is to make 'blocks' and add them to the blockchain and also to store the complete blockchain data. These blocks contain information about posts, comments, votes and currency transfers.[1]

Actually, I think it is best if you read the article: https://www.steem.center/index.php?title=Steem_Witness before I repeat everything.

Now - this however is only the technical part. Witnesses, in my opinion, have also another important role - and this role is to be the Voice of the people.

But I think I said it best in my post :)