Topic: just bought my first bitcoin; question about backing up (Read 437 times)

"bitcoins" are an abstraction that we humans use to make it easier to discuss transfer of control over value.  The "coins" themselves don't actually exist.  What does exist is a permanent record of every transaction that has ever occurred in the bitcoin system in a ledger called the "blockchain".  Every full node peer has a complete copy of this transaction ledger.  What a wallet contains are the private keys that allow you to reassign value in that ledger to someone else's control.

When you backup your "wallet" to physical medium, what you are actually doing is backing up those private keys.  As an analogy, if you think of private keys as a form of password, then you can see that you can have as many copies of the "wallet" in as many places as you want.  Each one is just another copy of the "passwords" that allow you control over some value in the blockchain.

While your "coins" are being stored at Coinbase, they are the ones that have control over the "coins" since they have the private keys.  You are trusting them to keep the private keys safe for you, you are trusting them to reassign the value in the blockchain at your request, and you are hoping that they will continue to be there to do both those things in the future.

Take some time to look into a few of the more popular wallet options.  Each has its own quirks, along with its own level of security and ease of use.  Then you can choose the wallet that best suits your needs.  Here are the popular ones to look into:

Paper wallet
Armory
Bitcoin-Qt
Electrum
MultiBit
https://blockchain.info/wallet

I signed up at coinbase, got my bank account verified and bought a bitcoin.
Is there some way I can back up coins on a physical medium in my possession?  Coinbase is probably not going to collapse or get hacked, but probably is not good enough.  And is it possible for a coin to live in two places, on the cloud and in a physical medium, both?