I wonder about the bitcoin and blockchain. I think I have understand the purpose of a blockchain. (security/decentralisation)
Ok we save transaction on blocks validate thanks to the proof of work.
But what I did not understand, how to get information from the blockChain. As for example to know "How mush Bitcoin Alice has ?"
Do we have to search all transactions of Alice saved on blocks and to calculate her balance ? Or is any other way (or something I have misandertood)
I know that there are tools to know the balance of an adress. But my question is how this tools works ? How they request the blockchain ?
Linking subject : What I understood is that we could save not only transaction in the bitcoin blockchain (or in the ethereum) There are dapps that use blockchain as ethereum to save there data. It is not a problem that to save many heterogeneous datas from differents dApps, mixing with transactions ?