A blockchain is a type of distributed ledger where transactions are grouped into “blocks” and linked (“chained”) using cryptographic hashes. This structure makes it very difficult to alter past transactions, thereby providing transparency and security.

Staking is locking up crypto assets (often in a Proof-of-Stake blockchain) to help validate transactions or secure the network, in return for rewards. It’s an alternative to mining (used in Proof-of-Work systems). However, returns are not guaranteed and there are risks (lock-up periods, network failure, etc.).