Sending a message using bitcoin

[Rora]

Hi Guys,

Im curious as to how I attach a message to a bitcoin payment? I would like to send a few btc to friends and would like to include a message is this possible?

Thank you!

[PrintMule]

Only way is to embed message in the payment itself, and by that it becomes public.

[Rora]

How do I do that exactly? I dont mind it being public.

[PrintMule]

How do I do that exactly? I dont mind it being public.

I mostly use blockchain.info online wallets so I don't know about your wallet software.

On blockchain.info when you choose "send money" you can select a "custom transaction" option and write a public note there.

[DannyHamilton]

The bitcoin protocol does not support messages.

The website blockchain.info has created their own database separate from the bitcoin network.  In this database of theirs, they allow their users to create a message when sending a bitcoin payment.  blockchain.info then stores that message in their own database, and broadcasts the transaction without the message onto the bitcoin network.  Individuals can then look at the blockchain.info website and see the messages that the blockchain.info users have created.

These messages aren't stored or visible anywhere else.

[fghj]

In theory you can embed messages into transactions but it's frowned upon because it bloats blockchain. Most clients have "sign message" functionality, you could use instead, sign some message using address (technically private key corresponding to that address) used in your transaction and sent message with signature to their email.
Note: you should sign only unambiguous messages and avoid signing stuff that looks like random crap you got from Nigerian prince.

Messages are sometimes embedded into transactions that go into blockchain if it's important to have proof that something was written around the time block was mined, most people pay extra miners fee for this and embed hash of their message for privacy and/or to have less bloat.

[Rora]

Thank you for the responses guys! I was hoping to send a few btc and sign it using some numbers only. I will play around with blockchain.info.

Thanks again!