Prom Explaining : sequencers
Sequencers are one of the most important components of the system since they essentially control the entire "rolling up" mechanism.
To put it simply and maintain the proper flow from L2 to L1, a sequencer functions as a traffic controller of transactions within the rollup architecture.
Getting transactions out of a Layer 2 mempool and getting them ready to be submitted to the Ethereum mainnet is the responsibility of a sequencer. The transactions are ordered, verified, and bundled into a single batch as part of this preparation. Then, this batch is sent as a single transaction to Ethereum.
