In multibit, you can export the private keys from a wallet into a basic text document (*.key).
It will look something like this:
# KEEP YOUR PRIVATE KEYS SAFE ! # Anyone who can read this file can spend your bitcoin. # # Format: # <Base58 encoded private key>[<whitespace>[<key createdAt>]] # # The Base58 encoded private keys are the same format as # produced by the Satoshi client/ sipa dumpprivkey utility. # # Key createdAt is in UTC format as specified by ISO 8601 # e.g: 2011-12-31T16:42:00Z . The century, 'T' and 'Z' are mandatory # KyBn........................................... 2014-06-06T04:26:48Z # End of private keys
[The series of dots is the key, but I censored out the majority of it.]
I have read this post on a similar question, but I am confused about one particular thing: If I have some transactions after the export, more or new private keys will be created, which will mean that I can no longer depend on this set of private keys to regain access to the funds. Is this correct?
My main question is, how exactly can I recover the funds for a particular address with only this private key (or set of private keys) (not specifically in multibit, but generally)? Do all clients and online wallets have an import private key option? What is done behind the scenes with this private key to find the public key and the address?