Understanding the data structure

A blockchain can also be defined as a sequence of blocks containing data that are chained together. There are two types of data:

• Transactions
• Block information (also called metadata)

The transaction section is built by gathering all of the transactions that happened in a certain period of time and gathered in the block. If I send you one Bitcoin, this transaction will be part of the transaction section. Three fields are consistently active:

• The recipient
• The sender
• The amount

When I send you one Bitcoin using the Bitcoin blockchain, the transaction is composed as follows:

• The recipient is your account (your Bitcoin address).
• The sender is my account (my Bitcoin address).
• The amount is 1 Bitcoin.

An example of a Bitcoin address is 3QSuhbsJUZJRgYX965CwMHgsdaU8KuTg4H.

Once all of the transactions are filled in the block, the block is hashed...