Bitcoin's blockchain technology is the foundation of the entire cryptocurrency system. Here are key aspects:

1. **Decentralization:** The Bitcoin blockchain is maintained by a distributed network of nodes (computers) around the world. No central authority controls it, providing resilience against censorship and single points of failure.

2. **Blocks and Transactions:** The blockchain is a chain of blocks, with each block containing a list of transactions. Transactions are grouped into blocks and added to the chain in a sequential, chronological order.

3. **Consensus Mechanism:** Bitcoin uses a proof-of-work consensus mechanism, where miners compete to solve complex mathematical puzzles to validate transactions and add them to the blockchain. This process ensures security and immutability.

4. **Mining Rewards:** Miners are rewarded with newly minted bitcoins and transaction fees for their efforts. This process also serves to introduce new bitcoins into circulation at a controlled rate.

5. **Immutability:** Once a block is added to the blockchain, it is extremely difficult to alter previous blocks. This immutability enhances the security and integrity of the transaction history.

6. **Hash Functions:** Cryptographic hash functions are used to link each block to the previous one, creating a secure and verifiable chain. Any change to a block would require recalculating subsequent blocks, making tampering highly impractical.

7. **Public and Private Keys:** Bitcoin transactions involve the use of cryptographic keys. A user's public key serves as their address, visible to others, while the private key is kept secret and is used to sign transactions, providing ownership and control.

8. **Limited Supply:** Bitcoin's protocol dictates a capped supply of 21 million bitcoins, creating scarcity similar to precious metals like gold. This feature is programmed into the blockchain to control inflation.

Understanding these foundational elements provides insight into how Bitcoin's blockchain ensures trustless and secure transactions in a decentralized manner.