Blockspace

Every blockchain can include only so much data or computation per block: Bitcoin limits block weight, Ethereum targets a gas amount per block, and other chains have their own ceilings. That capacity is blockspace. Users compete for it by attaching fees, and block producers fill each block with the transactions that pay best.

Thinking of blockspace as a product helps explain crypto economics. Demand for it, from payments, trading, NFTs or inscriptions, drives fee revenue, which pays for security. Layer 1s compete on how much blockspace they offer and at what price, rollups buy blockspace from Ethereum to post their data, and MEV builders bid for the best positions inside a block.

Supply is not simply a dial to turn up. Larger or faster blocks raise the cost of running a node and can weaken decentralisation, which is why Bitcoin's community fought over block size for years. Cheap, abundant blockspace can also produce low fee revenue, a concern for networks whose security depends on fees over time.