What is the difference between the "public key" and the "address" when looking at the backup section?
PUBLIC KEY is used by the system to process transactions from / to your wallet.
why is there an address and a public key? Other wallets do not do this.
The public address is a hashed version of the public key. Because the public key is made up of an extremely long string of numbers, it is compressed and shortened to form the public address. In effect, the private key generates the public key which, in turn, generates the public address. When two people enter into an agreement where one sends the other tokens or coins, they reveal their public addresses to each other. The public address is like a bank account number. The sender needs the number to be able to send the funds to the recipient who will then be able to spend or withdraw it with his private key. The recipient can also verify the sender’s batch of coins using the sender’s public address that will be displayed on his or her screen.
Although the public key and address are worked out from the private key, the reverse case is nearly impossible. The cryptocurrency network stays secure by using complicated mathematical functions to ensure that a private key is not able to be worked out from the public key, especially since the public key and its hash version are seen by everyone on the network. Since its impossible to regenerate the private key from public key or address, if a user loses his private key, any bitcoin or altcoin located at his public address will be inaccessible forever. On the other hand, a user who loses his public key can have it recreated with the seed phrase.
I'm posting this link as another reference:
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