Block
Conjunto de transações agrupadas e registradas juntas em uma blockchain; blocos são encadeados em sequência para formar o histórico da rede.
Key points
- A block is a set of transactions grouped and recorded together on a blockchain, along with a cryptographic summary of the previous block.
- Blocks are chained in sequence, forming the chain that gives the technology its name and preserves the order of the history.
- Each block has limited capacity, which creates competition for space and influences transaction fees.
What is a block?
A block is the basic unit of record on a blockchain. Instead of recording each transaction in isolation, the network groups them into blocks, which are validated and added to the history one after another. Each block carries a set of transactions and a reference to the previous block, stitching the records into a continuous, ordered sequence.
How it works
When transactions are submitted, they wait until they are included in a block. Miners or validators select pending transactions, assemble a block and, following the network's consensus rules, add it to the chain. Each block includes the hash of the previous one, so altering an old block would change all the following ones, making fraud evident.
The content of a block is usually summarized by a hash structure, such as a Merkle tree, which makes it possible to verify the inclusion of a transaction without examining all the others. Besides the transactions, the block carries control information, such as the creation time and the data proving the work or validation performed.
Since each block has a limited size, not all pending transactions fit right away. This creates competition for space, in which transactions offering higher fees tend to be included first.
Why it matters
The block is the piece that organizes and orders a network's transactions. For anyone sending payments, understanding that confirmation depends on the transaction entering a block explains why there is a waiting time and why higher fees speed up inclusion during periods of congestion.
Limitations
The limited capacity of each block imposes a ceiling on the number of transactions per time interval, which can raise fees and delay confirmations during demand spikes. Increasing block size has trade-offs, such as requiring more resources from nodes, which makes this a delicate and often debated decision. That is why block size is one of the most discussed topics in the design of any blockchain, as it directly affects capacity and decentralization. </content> </invoke>