When you open up MetaMask or a hardware wallet and want to write your transaction to a chain, what actually happens?

You are dealing with a decentralized network, so there is no one place for you to go. So where do you go?

Some of us (me!) might be missing a key piece of understanding.

To write (or even view!) transactions on a chain, you must connect to a node.

I harbored a false assumption that the entire network nodes was made of up miners - computers writing blocks to the chain in exchange for tokens.

A significant fraction of blockchain nodes are actually not mining, but are just as important.

These "nodes" are just computers running the network protocol.

The protocol enables computers to store a local copy of the chain, broadcast new transactions, and listen for broadcasted transactions from other nodes.

This is the real mind blowing thing about decentralized networks -

There is no one source of truth. When you want to access information on the blockchain, or make a new transaction, you must go use somebody else's copy!

While this is not necessarily a bad thing, it encourages people to run their own nodes to become truly autonomous.

What is really happening when you make a transaction

• To make a transaction, you connect to a network node, allowing you to scan the public address you are interacting with, and authorize the transfer of funds via your private key.

• You can do this with your own node, but if you are not running one, you must connect to something. Most likely, you are connecting to the node which your wallet provider is running.

• The node validates your transaction (you must have enough balance in the address), and then broadcasts it to other nodes.

• Once all nodes agree on the transaction, it is placed in a temporary pool, which miners then draw from to actually write a block of transactions to the chain in exchange for tokens.