Backing up wallet

[coinsgod]

Do you only need to backup the 12 letter seed words and the private key, or both the public & private key?

[TryNinja]

If you have a HD wallet (the one that gives you a seed of 12 words), you will only need to backup those 12 words. They are the one used to recover all the addresses from that wallet.

If you have a single address wallet, you will have to backup the private key that belongs to that address.

[timerland]

Do you only need to backup the 12 letter seed words and the private key, or both the public & private key?

Back up the 12 letter word, because that is how your whole wallet derives from.

If you only backup a private key then it could potentially mean that you lose out on coins that are sent to your other addresses - there is no means of getting your other addresses private keys with one of your private keys.

And you don't need to back up your public key, no. The public key can be derived from the private key at any given moment using sites like bitaddress. Run it offline if you want to have more security, but it's not necessary if it's just for an online wallet anyways.

[aizen10]

Do you only need to backup the 12 letter seed words and the private key, or both the public & private key?

absolutely yes. back up them both because those key are very important to retrieve your wallet and it wont give you hard time in future to accessing it on the other gadgets. meanwhile after you backed up those key (12 word seed) and private key. save it in safeties place on your home and never DO share that information to the others, it has a possibilities that you got hacked in future if you that.