Block Weight

Block weight is a concept introduced in the Bitcoin network through the SegWit (Segregated Witness) protocol upgrade. It is a measure of the size of a block, taking into account the weight of different components within the block, such as transaction inputs, outputs, and witness data. 

The purpose of block weight is to provide a more accurate representation of the computational resources required to process a block, as witness data (signatures and scripts) can be processed separately from the rest of the transaction data. By assigning different weights to these components, the SegWit protocol aims to incentivize the inclusion of more transactions per block while maintaining network security and decentralization. Block weight is calculated using a formula that assigns a weight of 4 to transaction data and a weight of 1 to witness data.