What is Blockchain Explorer?

What is Blockchain Explorer?
Blockchain Explorer is a search tool of the blockchain, and it is also a website, which was designed for users to browse and query information on the blockchain.
Blockchain needs a medium for users to see the situation on-chain, and the blockchain explorer is this medium. In the blockchain explorer, you only need to enter the TxHash of a transaction, wallet address or contract address, etc., to query their detailed information.
Commonly used Blockchain Explorer:
zkSync Era ∎ : https://explorer.zksync.io/
Polygon(Matic): https://polygonscan.com/
Avalanche C-Chain: https://avascan.info/
Filecoin FVM: https://filscan.io/
Scroll: https://blockscout.scroll.io/