[phendrenad2]

Really interested to learn those two terms - "market maker", "liquidity provider". I think I kinda understand the second one (traders who are bringing money from outside the market). Does anyone know where I can read more about this kind of thing?

[Misdicorl]

A market maker is an entity which isn't interested in the underlying assets at all. Their goal is to always end with a 0 asset, all cash balance sheet (over some small time interval). Their goal is to buy X at $100 and sell it at $100.01 a million times a day.

`Liquidity providing` is the side of the trade which had a `resting order` on the order book which traded against a new order (the liquidity taker). Various exchanges have various different fee schedules for your designation as a market maker, how much volume you do, whether you are taking or supplying liquidity, and what kind of order you are placing.

[lrem]

I'm pretty sure Wikipedia has you covered... But TL;DR: traders that always have a buy and sell transaction active, making sure the market allows to buy/sell instantly at any time.