You can export your private keys from a MultiBit Classic wallet into a file (using the 'Tools | Export private keys' option) and, as long as you do not manually create new receiving addresses, you can use the private key file as a backup for the wallet.
If something happened to your wallet and you want to recreate it do the following:
Problem solved! How can I thank you?
MultiBit Classic is "donationware" and all donations go towards development and server costs.
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