LESSON 1 / 4 · 6 MIN
Blocks: what the chain records
Know what a block contains and what on-chain data can and cannot tell you.
Bitcoin's ledger is a chain of blocks. Roughly every ten minutes a miner adds a new block with the latest transactions; that is about 144 blocks a day. Every transfer — who sent how much to which address — is public and stays there forever.
- ▸What the chain shows: transfers between addresses, fees paid, block size and timing, total supply.
- ▸What it does not show: who is behind an address, the price, and anything that happens inside an exchange — most trading never touches the chain.
Key idea
On-chain data is complete for the network and blind for the exchanges. That is why this course combines chain data (module 1) with exchange data (modules 2–4).
Tip
Fees rise when many people want to move bitcoin at the same time. A spike in fees often coincides with a big move in price or a rush to exchanges.
On the site · /block-explorer
Open the block explorer and look at the latest block: how many transactions and how much in fees?
Open it on the site →Check yourself
Can you see on-chain how much bitcoin someone bought on an exchange today?