Ethereum is an open-source, globally decentralized computing infrastructure that executes programs called smart contracts. It uses a blockchain to synchronize and store the system state along with a cryptocurrency called ether to meter and constrain execution resource cost.
The Ethereum platform enables developers to build powerful applications with built-in economic functions. Additionally, it provides continuous uptime and eliminates issues of censorship, third-party interference,and counterparty risk.
Why not bitcoin? A stack based language that is Turing incomplete is not flexible/expressive enough to build various apps, only narrow domain specific apps that relate to currency transactions.
Ethereum as general purpose blockchain to build apps on. Compare to summer of 2014 - a chain for every app. Developers have to worry about the platform basics rather than focus on their application. Same as early years of computing. By having a common standard, flexible platform, developers can build their app and not worry about the platform details (too much, ideally)
High level, expressive flexible language that abstracts the details of the security model, the blockchain mechanism, the consensus algorithm.
Towards the end of 2013, a young programmer and bitcoin enthusiast, Vitalik Buterin started thinking about further extending the capabilities of Bitcoin and Mastercoin (an overlay protocol that extended Bitcoin to offer rudimentary smart contracts). In October 2013, Vitalik proposed a more generalized approach to the Mastercoin team, one that allowed flexible and scriptable (but not Turing-complete) contracts to replace the specialized contract language of Mastercoin. While the Mastercoin team was impressed, this proposal was too radical a change to fit into their development roadmap.
In December 2013, Vitalik started sharing a "white paper", which outlined the idea behind Ethereum: a Turing-complete programmable and general purpose blockchain. A few dozen people saw this early draft and started offering feedback to Vitalik, helping him gradually evolve it.
Both of the authors of this book commented on this early draft. Andreas M. Antonopoulos, received a copy in his role as a host of the "Let’s Talk Bitcoin" podcast. Andreas was intrigued by the idea and asked Vitalik many questions about the use of a separate blockchain to enforce consesus rules on smart contract execution and the implications of a Turing-complete language. Andreas continued to follow Ethereum’s progress with great interest but was in the early stages of writing his book "Mastering Bitcoin" and did not participate directly in Ethereum until much later.
The other author of this book however, Dr. Gavin Wood, was one of the first people to reach out to Vitalik and offer to help with his C++ programming skills and became Ethereum’s co-founder, co-designer and CTO.
As Vitalik recounts in his "Ethereum Prehistory" post:
This was the time when the Ethereum protocol was entirely my own creation. From here on, however, new participants started to join the fold. By far the most prominent on the protocol side was Gavin Wood.
…
Gavin can also be largely credited for the subtle change in vision from viewing Ethereum as a platform for building programmable money, with blockchain-based contracts that can hold digital assets and transfer them according to pre-set rules, to a general-purpose computing platform. This started with subtle changes in emphasis and terminology, and later this influence became stronger with the increasing emphasis on the “Web 3” ensemble, which saw Ethereum as being one piece of a suite of decentralized technologies, the other two being Whisper and Swarm.
Starting in December 2013, Vitalik and Gavin refined and evolved the idea, together building the protocol layer that became Ethereum.
Much like Satoshi, Vitalik and Gavin didn’t just invent a new technology, they combined new inventions with existing technologies in a novel way and delivered the prototype code to prove their ideas to the world.
Ethereum was born.
Vitalik Buterin’s article "A Prehistory of Ethereum" was published in September 2017 and provides a fascinating first-person view of Ethereum’s earliest moments.
You can read it at http://vitalik.ca/general/2017/09/14/prehistory.html
What are smart contracts? Neither contracts nor smart. PROGRAMS.
Programmers perspective - what is diff about Ethereum
it offers a programing language, development frameworks and execution platform that are very familiar. Solidity modeled after javascript (??), strong javascript integration, common scaffold patterns (truffle), in browser DOM, tight integrations with popular UI/UX frameworks.
Double edged sword - language appears simple and aims to abstract the platforms security consideration. In practice, writing secure code in this language is very difficult and requires awareness of security design patterns involving concurrency, re-entrancy and distributed systems. Moves quickly and is not well understood. False sense of security leads to losses.
What does this book contain:
How Ethereum works How to program using Ethereum as a platform.
From a simple contract, all the way down to how it runs in the EVM, and then back up again.