Define the “Mempool” and Its Role in a Public Blockchain’s Transaction Lifecycle

The mempool (memory pool) is a waiting area for unconfirmed transactions that have been broadcast to the network but not yet included in a block. It acts as a staging area where transactions wait to be picked up by a miner or validator.

The mempool is public, which is what enables front-runners to observe pending transactions and create their own counter-transactions with higher fees.