Linked Questions

5
votes
1answer
8k views

How does a blockchain store any data?

I read here that since Bitcoin is a networked ledger, it is a good way to back up data. I would like to know two things: How does a blockchain store 'any' data? I would like to know more about a ...
0
votes
1answer
916 views

Why OP_RETURN should be used instead of raw data?

I've read this great Explanation of what an OP_RETURN transaction looks like and now I have only one question. Imagine that someone want to store some data in Bitcoin's blockchain. Why should he use ...
0
votes
3answers
481 views

Pictures and non-transaction data in block chain

It is well known that non transaction related information has found its way into the block chain. This raises multiple questions: (1) How was it done, and is it still possible (2) If someone where to ...
3
votes
1answer
347 views

Does an OP_RETURN script always need another output within the transaction?

I was reading this: Explanation of what an OP_RETURN transaction looks like and I wondered if the second output "value" : 0.00200000, was at all necessary. Can I just have a OP_RETURN with a 0 output ...
2
votes
1answer
507 views

OP_RETURN in a coinbase transaction?

Hey looking at this transaction I'm confused why there are two outputs and why one of them is labelled with OP_RETURN
2
votes
1answer
242 views

Upper bound on the Bitcoin transaction size [duplicate]

Assume that I want to store some arbitrary data on the Bitcoin blockchain via a single transaction. Question: Is there any upper bound on the size of data I want to send via a single transaction? -...
2
votes
1answer
154 views

Question regarding the number of bytes in an OP_RETURN transaction

I was reading this very useful explanation of what an OP_RETURN transaction looks like and got tripped up by part of it. "hex" : "6a13636861726c6579206c6f766573206865696469" This first ...
0
votes
1answer
53 views

Can a client leave its mark on the blockchain?

Would it be possible for a client (eg the core client) to leave its mark in the form of META data on the blockchain or even in the mempool so that we know that this client was used to create or send ...
0
votes
1answer
57 views

Proving the margin of error of a block timestamp

In the Bitcoin wiki: Block times are accurate only to within an hour or two. is a bit vague. Is it possible to prove that an arbitrary accepted block timestamp is within x seconds of the real-...
0
votes
0answers
19 views

Getting Started with a Hello World Node.js App making an API call to bitcoin.org

I have been reading around trying to find where/how you can attach a SHA256 or MD5 hash (i.e. a small chunk of data) to a Bitcoin transaction, which led to OP_RETURN, but I have yet to see exactly how ...