What is the difference between a contract and a futures contract?

Could you please elaborate on the distinction between a contract and a futures contract? I've been trying to grasp the nuances of these financial instruments, but I'm still a bit hazy on the specifics. In my understanding, a contract is a legally binding agreement between two or more parties that outlines the terms and conditions of a transaction. However, when it comes to futures contracts, I'm not entirely clear on how they differ. Are futures contracts a subset of the broader category of contracts, or are they fundamentally different in nature? Furthermore, I'm curious about the role of futures contracts in the cryptocurrency and finance world. How do they work, and what are their primary uses? Are they primarily used for hedging purposes or for speculative trading? I'm eager to gain a deeper understanding of these concepts, so I hope you can shed some light on these matters. Thank you in advance for your assistance.