https://snakecharmers.ethereum.org/a-developers-guide-to-ethereum-pt-1/
[Last update: Nov. 28, 2022]
So, you’ve heard about this Ethereum thing and are ready to venture down the rabbit hole? This post will quickly cover some blockchain basics, then get you interacting with a simulated Ethereum node – reading block data, checking account balances, and sending transactions. Along the way, we’ll highlight the differences between traditional ways of building apps and this new decentralized paradigm.
This post aspires to be accessible to a wide range of developers. Python tools will be involved, but they are just a vehicle for the ideas – no problem if you are not a Python developer. I will, however, be making just a few assumptions about what you already know, so we can quickly move on the Ethereum-specific bits.
Assumptions:
pip, Python’s package installer.Again, if any of these are untrue, or you don’t plan to reproduce the code in this article, you can likely still follow along just fine.
There are many ways to describe Ethereum, but at its heart is a blockchain. Blockchains are made up of a series of blocks, so let’s start there. In the simplest terms, each block on the Ethereum blockchain is just some metadata and a list of transactions. In JSON format, that looks something like this:
{
"number": 1234567,
"hash": "0xabc123...",
"parentHash": "0xdef456...",
"miner": "0xa1b2c3...",
...,
"transactions": [...]
}
Each block has a reference to the block that came before it; the parentHash is simply the hash of the previous block.
Note: Ethereum makes regular use of hash functions to produce fixed-size values (“hashes”). Hashes play an important role in Ethereum, but you can safely think of them as unique IDs for now.
A blockchain is essentially a linked list; each block has a reference to the previous block.