A crypto address is a string of characters that represents a wallet that can send and receive cryptocurrency. It is akin to a real-life address, email or website. Every address is unique and denotes the location of a wallet on the blockchain.
Most blockchain addresses are difficult for humans to read, as they take the form of long random strings of letters and numbers. However, they are all unique, which poses no problems for computer networks.
Blockchain addresses are public and you can utilize a blockchain explorer to see the transactions in and out of an address. You can also see the amount of assets that the address has. The only exception are the privacy-based blockchains (eg. MoneroMonero (xmr)40$ 261.810.14%-0.67%-2.49%details and GrinGrin (grin)667$ 0.397650.01%-2.81%2.60%details).