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Sorry if these questions seem stupid but after a lot of research I still feel rather lost and confused !! I understand what is bitcoin and have a fairly good understanding of the basic blockchain idea but I have a hard time understanding some concepts. For example where can one download the source code for the blockchain ? How did Ethereum get the source code for the blockchain ? How can an update be "scheduled" for a specific block and not be implemented immediately ? Or how can one code apps for a blockchain platform like ethereum ?
I guess all these fall in the question, where can I find a thorough, complete explanation of the blockchain?