Bitcoin node is basically a storage device, such as a laptop or PC with internet access, which has the capacity to store the Bitcoin blockchain. The node passes the information from the user to the miner. The node also stores the Bitcoin blockchain.
These nodes are synchronized with each other. If there is one node that is offline for a certain period of time, that node will download the latest data from the other nodes when it reconnects to the internet.
It’s the same as Google Sheet, which you can access in View-only mode. If you have access, you can open the sheet online at any time.
If we end this analogy here, this is what is known as the lightweight client. However, a lightweight client cannot be called a node. To become a node, you must be a full client. A full client is a client who owns the blockchain and also shares blocks and transactions on the network.
Anyone who has sufficient storage space and is connected to the internet can run the node.
Nodes don’t have to mine Bitcoin. All miners are nodes, but not all nodes are miners. However, nodes are an important part of the ecosystem as they contribute to decentralization, as well as blockchain security. Thank you, node!