Having problem understanding how bitcoin works

[Jammy01]

I have been trying to understand how bitcoin works because I have zero knowledge about it, after reading some recommendations on the forum i found this https://learnmeabitcoin.com/beginners/how-does-bitcoin-work/

I am a bit confused on the part talking about how nodes mine transactions


What if different nodes mine a conflicting transaction at the same time (everyone has the transaction in their memory pool and no one as mined it) one node is meant to mine and kick conflicting transactions and updates it file which is sent to other nodes whereby other nodes kick conflicting transactions in there memory pool too

But what if two nodes mistakenly mine a conflicting transaction at the same time
I just want to know if that is possible


I'm a newbie I'm just trying to wrap my head around bitcoin, the write up may look somehow

[hmbdofficial]

Your question has been answered in so may thread on the board. Just a quick search can help you out, however it’s possible that two miners can find valid blocks almost the sametime and those block can actually contain conflicting transactions. And it’s one of the situations bitcoin is designed to handle.
Just how that bitcoin doesn’t try to stop this from happening. The node follows the chain with the most cumulative proof of work. As more blocks are minded on one branch, that branch eventually wins, and others become stale. And the transaction in that branch will not be confirmed. Therefore two conflicting transactions can effectively be mined at the same time but only one get confirmed, the consensus mechanism is what usually resolves the temporary disagreement

[Donneski]

This your your topic I think should've been better made in the Bitcoin discussion board but since there are some technicalities in your question, maybe the moderators will leave it here.

Now to your question, I'd have loved to intensively explain how nodes work, however, I think it'll be better I refer you to few threads that had extensively discussed them in the forum, in them, you'll also find the contributions of very experienced members which will give you a better insight of what you really want to know.
First among them is this thread by @Fivestar4everMVP titled Understanding Bitcoin Nodes, Its Types, Functions and Benefits.

You can also check these threads below
https://bitcointalk.org/index.php?topic=5500955.0
https://bitcointalk.org/index.php?topic=5484089.0
https://bitcointalk.org/index.php?topic=5523879.0

I hope you get the clarity you seek after reading through the threads.

[Cookdata]

I am a bit confused on the part talking about how nodes mine transactions

I get your question but nodes does not mine Bitcoin transactions, miners does. The node helps validate transactions and update the ledger after transactions are mined.

But what if two nodes mistakenly mine a conflicting transaction at the same time
I just want to know if that is possible

Two miners, not nodes can mine a conflicting transaction but we can't have two block height on the network, one with the longest chain as proof of work is going to be the valid block and the other one will become a stale block.

PS: Miners are nodes but not all nodes are miners. If you continue to use node, people will assume you are referring to ordinary nodes but the context of your questions points to miners.
Read: https://learnmeabitcoin.com/technical/blockchain/chain-reorganization/

[Mia Chloe]

~snip

I can't vividly remember but I think I made a few replies concerning this in another post someone here has left a link to some posts that actually discuss these stuff about conflicting transactions. First off understand every miner has his own mempool it's after they confirm that it kinda becomes like a general one.

If a conflict like that ever happens the miner that has the heaviest transaction volume will be accepted against the other conflicting confirmation almost similar to the chain with more validations becoming the valid one.

[Stalker22]

~
But what if two nodes mistakenly mine a conflicting transaction at the same time
I just want to know if that is possible

Yes, it is possible.  I dont know exactly how common it is these days, but in the early days, it happened more often because propagation was slow, leading to frequent temporary splits.  And just as hmbdofficial and Cookdata explained, the longer chain wins, and all transactions from the discarded block return to the mempool.  Any conflicting double-spend transaction is rejected by the network because because its source UTXO no longer exists on the main chain.

[Mia Chloe]

PS: Miners are nodes but not all nodes are miners. If you continue to use node, people will assume you are referring to ordinary nodes but the context of your questions points to miners.
Read: https://learnmeabitcoin.com/technical/blockchain/chain-reorganization/

This is actually valid because nodes don't really interact directly in stuff like these they just share and store what the chain records more like public ledger. The catch for this conflict is most times the miner with a more efficient propagation and hashrate will most likely win the fees.

Ordinary nodes can't do anything because based on the conflict the node will accept the one that gets propagated to it first and if the issue is solved it kinda resyncs back to meet the normal conditions.

[Upgrade00]

I have been trying to understand how bitcoin works because I have zero knowledge about it, after reading some recommendations on the forum i found this https://learnmeabitcoin.com/beginners/how-does-bitcoin-work/

https://learnmeabitcoin.com/beginners/guide/mining/
The above section in the link you shared on mining is probably the part that led you to use nodes for miners interchangeably, cause that's how they used it on the page. All miners are nodes, they need a copy of the blockchain/mempool to attempt to "confirm" transactions, which is the mining process.
For clarity, the process of confirming blocks is mining, and those who attempt to do so are miners.

Individual miners may choose not to run a node if they're connecting to a mining pool that already runs one or several.

[goldkingcoiner]

I have been trying to understand how bitcoin works because I have zero knowledge about it, after reading some recommendations on the forum i found this https://learnmeabitcoin.com/beginners/how-does-bitcoin-work/

I am a bit confused on the part talking about how nodes mine transactions

What if different nodes mine a conflicting transaction at the same time (everyone has the transaction in their memory pool and no one as mined it) one node is meant to mine and kick conflicting transactions and updates it file which is sent to other nodes whereby other nodes kick conflicting transactions in there memory pool too

But what if two nodes mistakenly mine a conflicting transaction at the same time
I just want to know if that is possible


I'm a newbie I'm just trying to wrap my head around bitcoin, the write up may look somehow

Nodes do not mine transactions. And Bitcoin deliberately allows temporary disagreement between nodes and has a way to resolve it.

Miners mine blocks containing transactions. Just because a transaction is in the mempool does not mean it has been permanently accepted into the blockchain. That is why people talk about "confirmations". The more confirmations the less likely a competing chain will replace it.

Mempool: "Here are the transactions that I know of and consider valid."
Mining: "I am making a block candidate and trying to find proof-of-work by using some of these transactions"
Blockchain: "Here is the history of what the network has agreed on."

[Jammy01]

I am a bit confused on the part talking about how nodes mine transactions

I get your question but nodes does not mine Bitcoin transactions, miners does. The node helps validate transactions and update the ledger after transactions are mined.

But what if two nodes mistakenly mine a conflicting transaction at the same time
I just want to know if that is possible

Two miners, not nodes can mine a conflicting transaction but we can't have two block height on the network, one with the longest chain as proof of work is going to be the valid block and the other one will become a stale block.

PS: Miners are nodes but not all nodes are miners. If you continue to use node, people will assume you are referring to ordinary nodes but the context of your questions points to miners.
Read: https://learnmeabitcoin.com/technical/blockchain/chain-reorganization/

Thank you I get it now

[Alpha Marine]

You're talking about miners, not nodes. Nodes don't mine or confirm a transaction. What they do is validate, store and pass on transactions and blocks across the peer-to-peer network. Nodes help secure the system. The more nodes in the network, the more difficult it would be for anybody to control, meaning it would be more decentralised and more secured. In simply terms, it is easier to hack and gain control of ten systems, than it is to gain control of a hundred systems. 
While miners are the ones who confirm new transactions and mine new blocks.

Your actual question has been answered, I just wanted to clarify the difference bwteen nodes and miners. You should probably read more on the both of them to have a better understanding of the difference.

[tbct_mt2]

I have been trying to understand how bitcoin works because I have zero knowledge about it, after reading some recommendations on the forum i found this https://learnmeabitcoin.com/beginners/how-does-bitcoin-work/

I am a bit confused on the part talking about how nodes mine transactions

Bitcoin nodes are not Bitcoin miners and nodes don't mine Bitcoin block or confirm transactions, Bitcoin miners do that. You must also know that Bitcoin transactions are confirmed, not mined, while what are mined are Bitcoin blocks.

Bitcoin miners mine Bitcoin block and confirm transactions while Bitcoin nodes relay block information including transactions and relay these information to other Bitcoin nodes. Bitcoin miners and Bitcoin nodes do different tasks on the Bitcoin network but there is an overlap as Bitcoin miners can run their own Bitcoin nodes too.

https://learnmeabitcoin.com/beginners/guide/node/
https://learnmeabitcoin.com/beginners/guide/network/
https://github.com/bitcoinbook/bitcoinbook/blob/develop/ch10_network.adoc
https://github.com/bitcoinbook/bitcoinbook/blob/develop/ch12_mining.adoc
https://github.com/bitcoinbook/bitcoinbook/blob/develop/ch06_transactions.adoc

[promise444c5]

But what if two nodes mistakenly mine a conflicting transaction at the same time
I just want to know if that is possible


I'm a newbie I'm just trying to wrap my head around bitcoin, the write up may look somehow

It’s fine, most people here were once a newbie except those with some knowledge before joining and the devs .

There’s no need to correct “node” again, so I will just comment based on how you understood it..

Not sure if what you meant is Invalid or conflicting

The possibility of what you mentioned is slim if it made it( two block containing conflicting transaction at the same block height) but still possible, that will be solved by longest chain and one of the two would be confirmed afterwards ..

If  you meant invalid transaction ( in both blocks ) .. at the end, both will be rejected by up-to-date nodes and the valid transactions in the particular blocks will have to be mined by another miner running the latest node .

[Mia Chloe]

There’s no need to correct “node” again, so I will just comment based on how you understood it..

Sometimes it's necessary to distinguish between nodes and miners especially in sensitive questions like these. For instance it's quite safe to say nodes will accept literally almost anything that is valid because they are more like a public ledger unlike miners that can choose what they wanna add till it's been accepted by others before they too are compelled to sync.

If  you meant invalid transaction ( in both blocks ) .. at the end, both will be rejected by up-to-date nodes and the valid transactions in the particular blocks will have to be mined by another miner running the latest node .

Can you please clarify what you mean here ? I don't really get it in total especially both getting rejected because I don't think so.

[promise444c5]

There’s no need to correct “node” again, so I will just comment based on how you understood it..

Sometimes it's necessary to distinguish between nodes and miners especially in sensitive questions like these.

I was directing the statement to myself   , like I don’t need to repeat what others had  explain already on the thread..

If  you meant invalid transaction ( in both blocks ) .. at the end, both will be rejected by up-to-date nodes and the valid transactions in the particular blocks will have to be mined by another miner running the latest node .

Can you please clarify what you mean here ? I don't really get it in total especially both getting rejected because I don't think so.

Invalid transactions that mostly escape normal mempool checks  and eventually get mined can be the result of nodes running non-up-to-date consensus rules or bugs in affected nodes, among others ..

Hence, “invalid” can mean invalid under the current consensus rules or invalid as a result of a bug.

So if there’s something rare [as mentioned] like two miners mining blocks containing invalid transactions.. both blocks will be rejected by up-to-date nodes if the transactions violate a consensus rule they enforce.

[Comeacross]

But what if two nodes mistakenly mine a conflicting transaction at the same time
I just want to know if that is possible

This exact scenario was discussed in my previous thread What happen when 2 miners confirm different versions of my transaction same tim?

Yes, It's possible for two nodes to mine conflicting transactions at the same block height at the same time due network latency and that's how we get temporary fork since the network resolve the issue via the longest chain rule. Scenarios like this is the reason why we have to wait for confirmation after broadcasting transactions to avoid double spend issues. You can check the thread to read more explanatory posts on this issue.

[oll]

I have been trying to understand how bitcoin works because I have zero knowledge about it, after reading some recommendations on the
...
I'm a newbie I'm just trying to wrap my head around bitcoin, the write up may look somehow

I highly recommend you watch this video about Bitcoin and how it works. I've seen many videos with fancy effects, but never one as informative and engaging as this one.
The author doesn't make flashy videos, but explains things incredibly simply and, I would even say, captivatingly. This is the video that really helped me understand all the basic principles of Bitcoin. And I always recommend it to friends and acquaintances who have even the slightest interest in cryptocurrencies or Bitcoin.

https://youtu.be/bBC-nXj3Ng4?is=5zJSLbsvpWJdUY2F

This is a very common video and I think you can find it translated if English is not your native language.