Actually, many people still have a bit of a fuzzy understanding of the structure of the Bitcoin network, so today I want to talk about nodes. Simply put, a node is any computer or device connected to the Bitcoin network, communicating via P2P protocol, jointly maintaining the security and decentralization of the entire network.

First, let's talk about the most important—full nodes. These nodes are the backbone of the Bitcoin network; they store the complete blockchain data and verify all transactions and blocks to ensure they follow consensus rules. In plain terms, these nodes are guarding Bitcoin's rules. Running a full node requires certain hardware investments: at least 200GB of disk space, 2GB of RAM, and a stable internet connection. The bandwidth can be quite heavy, with uploads and downloads possibly reaching dozens of GB per month. It's best to run it 24/7, but at minimum, at least 6 hours a day. Currently, there are nearly 10k public nodes running across the network, although many hidden nodes operate behind firewalls via protocols like Tor.

Next are super nodes or listening nodes. These are essentially visible full nodes that are online 24/7, handling a large number of connections and acting as data relays. Compared to hidden full nodes, super nodes require more powerful computing capabilities and better network conditions.

Miner nodes are a different matter. To participate in mining competition, miners need specialized hardware and software. Individual miners can mine solo or join mining pools to share computing power. Interestingly, a mining pool only needs an administrator to run a single full node; other miners do not need to.

There’s also a category called lightweight clients (SPV clients), like many wallets. They do not store the full blockchain but only verify transactions relevant to themselves, relying on full nodes for information. The advantage is resource savings, but the cost is not contributing to network security.

Here’s a clarification—running a full node and running a mining node are two different things. Anyone can run a full node, but mining requires specialized equipment. Moreover, miners first collect unconfirmed transactions from full nodes before attempting to package and mine blocks. Ultimately, it still depends on full nodes for verification. So, the nodes that truly maintain consensus rules are these validation nodes, not the miners.

Honestly, although running a full node doesn’t provide direct financial rewards, it offers users real security and privacy protection. Full nodes ensure transaction rules are followed, preventing frauds like double-spending attacks. Most importantly, you have complete control over your funds without trusting any third party. For those who truly believe in decentralization, this is worth it.