Mempool

The memory pool (aka mempool) is a node's view of unconfirmed transactions that have been broadcast to the network. Not all nodes will have the same mempool due to the amount of memory they've allocated, and specific rules that may censor transactions. Above is our node's unconfirmed transactions and sum of their serialized virtual sizes (i.e. includes segwit discount). We run default Bitcoin Core settings.

Unit:  Transactions, Bytes

Source:  BitcoinVisuals node (bitcoind)