Block: typically holds a transaction list, timestamp, the previous block's hash, and its own hash. Because of the previous hash, blocks link together into a chain — so editing a block in the middle makes its hash stop matching the blocks that follow it.
Visual Flow
Block #1 → Hash A → Block #2 uses Hash A → Hash B → Block #3 uses Hash B
text
{
"block_number": 1024,
"timestamp": "2026-05-04T10:00:00Z",
"transactions": [
"Sai sends 0.01 coin to Thuta",
"Studio contract records a certificate"
],
"previous_hash": "0xabc123...",
"hash": "0xdef456..."
}You should see
A block is a record package; a chain is what you get when those packages are locked together in order with cryptographic fingerprints.