The blockchain is an incorruptible digital ledger of economic transactions that can be programmed to record not just financial transactions but virtually everything of value (by [Don Tapscott](https://www.linkedin.com/pulse/whats-next-generation-internet-surprise-its-all-don-tapscott)).
<fontcolor=#0099ffsize=3>**This is not a simple collection of Internet resources, but verified and organized data ensuring it's really suitable for your learning process and useful for your development and application.**</font>
A: A Merkle tree is a hash tree named after Ralph Merkle who patented the concept in 1979
(the patent expired in 2002). A hash tree is a generalization of hash lists or hash chains where every leaf node (in the tree) is labelled with a data block and every non-leaf node (in the tree)
is labelled with the crypto(graphic) hash of the labels of its child nodes. For more see the [Merkle tree](https://en.wikipedia.org/wiki/Merkle_tree) Wikipedia Article.
Note: By adding crypto(graphic) hash functions you can "merkelize" any data structure.
**Q: What's a Merkelized DAG (Directed Acyclic Graph)?**
**Bitcoin** is an experimental digital currency that enables instant payments to anyone, anywhere in the world. Bitcoin uses **peer-to-peer** technology to **operate with no central authority**: managing transactions and issuing money are carried out collectively by the network.
**Ethereum** is a **decentralized platform that runs smart contracts**: applications that run exactly as programmed without any possibility of downtime, censorship, fraud or third-party interference.
These apps run on a custom built **blockchain, an enormously powerful shared global infrastructure that can move value around and represent the ownership of property.**
- [The Hitchhiker's Guide to Smart Contracts in Ethereum](https://blog.zeppelin.solutions/the-hitchhikers-guide-to-smart-contracts-in-ethereum-848f08001f05)
**XuperChain**, the first open source project of XuperChain Lab, introduces a highly flexible blockchain architecture with great transaction performance.
**XuperChain** is the underlying solution for union networks with following highlight features:
**High Performance**
* Creative XuperModel technology makes contract execution and verification run parallelly.
* [Flexible authorization system](https://xuperchain.readthedocs.io/zh/latest/design_documents/permission_model.html) supports weight threshold, AK sets and could be easily extended.
**Multi-Language Support**: Support pluggable multi-language contract VM using [XuperBridge](https://xuperchain.readthedocs.io/zh/latest/design_documents/XuperBridge.html) technology.
+ [Comparation with Fabric and Ethereum](https://github.com/xuperchain/xuperchain/wiki/%E9%99%84-%E8%AF%84%E6%B5%8B%E6%95%B0%E6%8D%AE%E5%AF%B9%E6%AF%94)
- [**C#**: _Programming The Blockchain in C#_](https://programmingblockchain.gitbooks.io/programmingblockchain/)
- [**Crystal**: _Write your own blockchain and PoW algorithm using Crystal_](https://medium.com/@bradford_hamilton/write-your-own-blockchain-and-pow-algorithm-using-crystal-d53d5d9d0c52)
- [**C++**: _Blockchain from Scratch_](https://github.com/openblockchains/awesome-blockchains/tree/master/blockchain.cpp)
- [**Go: _Building Blockchain in Go_**](https://github.com/Jeiwan/blockchain_go) / [Chinese version 1](https://github.com/liuchengxu/blockchain-tutorial/blob/master/content/part-1/basic-prototype.md) / [Chinese version 2](https://zhangli1.gitbooks.io/dummies-for-blockchain/content/)
- [**Go**: _Building A Simple Blockchain with Go_](https://www.codementor.io/codehakase/building-a-simple-blockchain-with-go-k7crur06v)
- [**Go**: _Code your own blockchain in less than 200 lines of Go_](https://medium.com/@mycoralhealth/code-your-own-blockchain-in-less-than-200-lines-of-go-e296282bcffc)
- [**Go**: _Code your own blockchain mining algorithm in Go_](https://medium.com/@mycoralhealth/code-your-own-blockchain-mining-algorithm-in-go-82c6a71aba1f)
- [**Go**: _GoCoin - A full Bitcoin solution written in Go language (golang)_](https://github.com/piotrnar/gocoin)
- [**Go**: _GoChain - A basic implementation of blockchain in go_](https://github.com/crisadamo/gochain)
- [**Go**: _Having fun implementing a blockchain using Golang_](https://github.com/izqui/blockchain)
- [**Go**: _NaiveChain - A naive and simple implementation of blockchains_](https://github.com/kofj/naivechain)
- [**Java**: _Creating Your First Blockchain with Java_](https://medium.com/programmers-blockchain/create-simple-blockchain-java-tutorial-from-scratch-6eeed3cb03fa)
- [**Java**: _Write a blockchain with java_](https://www.jianshu.com/p/afd8c465c91a)
- [**JavaScript**: _A cryptocurrency implementation in less than 1500 lines of code_](https://github.com/conradoqg/naivecoin)
- [**JavaScript**: _Build your own Blockchain in JavaScript_](https://github.com/nambrot/blockchain-in-js)
- [**JavaScript**: _Code for Blockchain Demo_](https://github.com/seanjameshan/blockchain)
- [**JavaScript**: _Creating a blockchain with JavaScript_](https://github.com/SavjeeTutorials/SavjeeCoin)
- [**JavaScript**: _How To Launch Your Own Production-Ready Cryptocurrency_](https://hackernoon.com/how-to-launch-your-own-production-ready-cryptocurrency-ab97cb773371)
- [**JavaScript**: _Learn & Build a JavaScript Blockchain_](https://medium.com/digital-alchemy-holdings/learn-build-a-javascript-blockchain-part-1-ca61c285821e)
- [**Kotlin**: _Let’s implement a cryptocurrency in Kotlin_](https://medium.com/@vasilyf/lets-implement-a-cryptocurrency-in-kotlin-part-1-blockchain-8704069f8580)
- [**Python**: _A Practical Introduction to Blockchain with Python_](http://adilmoujahid.com/posts/2018/03/intro-blockchain-bitcoin-python/)
- [**Python**: _Build your own blockchain: a Python tutorial_](http://ecomunsing.com/build-your-own-blockchain)
- [**Python**: _Learn Blockchains by Building One_](https://hackernoon.com/learn-blockchains-by-building-one-117428612f46)
- [**Python**: _Let’s Build the Tiniest Blockchain_](https://medium.com/crypto-currently/lets-build-the-tiniest-blockchain-e70965a248b)
- [_Part 2 — Syncing Chains From Different Nodes_](https://bigishdata.com/2017/10/27/build-your-own-blockchain-part-2-syncing-chains-from-different-nodes/)
- [_Part 3 — Nodes that Mine_](https://bigishdata.com/2017/11/02/build-your-own-blockchain-part-3-writing-nodes-that-mine/)
- [_Part 4.1 — Bitcoin Proof of Work Difficulty Explained_](https://bigishdata.com/2017/11/13/how-to-build-a-blockchain-part-4-1-bitcoin-proof-of-work-difficulty-explained/)
- [_Part 4.2 — Ethereum Proof of Work Difficulty Explained_](https://bigishdata.com/2017/11/21/how-to-build-your-own-blockchain-part-4-2-ethereum-proof-of-work-difficulty-explained/)
- [**Ruby**: _Programming Blockchains Step-by-Step (Manuscripts Book Edition)_](https://github.com/yukimotopress/programming-blockchains-step-by-step)
- [**Scala**: _How to build a simple actor-based blockchain_](https://medium.freecodecamp.org/how-to-build-a-simple-actor-based-blockchain-aac1e996c177)
- [**TypeScript**: _Naivecoin: a tutorial for building a cryptocurrency_](https://lhartikk.github.io/)
- [_Minimal working blockchain_](https://lhartikk.github.io/jekyll/update/2017/07/14/chapter1.html)
- [_Proof of Work_](https://lhartikk.github.io/jekyll/update/2017/07/13/chapter2.html)
**Quorum** is an Ethereum-based distributed ledger protocol with transaction/contract privacy and new consensus mechanisms.
**Quorum** is a fork of [go-ethereum](https://github.com/ethereum/go-ethereum) and is updated in line with go-ethereum releases.
Key enhancements over go-ethereum:
***Privacy** - Quorum supports private transactions and private contracts through public/private state separation, and utilises peer-to-peer encrypted message exchanges (see [Constellation](https://github.com/jpmorganchase/constellation) and [Tessera](https://github.com/jpmorganchase/tessera)) for directed transfer of private data to network participants
***Alternative** Consensus Mechanisms - with no need for POW/POS in a permissioned network, Quorum instead offers multiple consensus mechanisms that are more appropriate for consortium chains:
***Raft-based Consensus** - a consensus model for faster blocktimes, transaction finality, and on-demand block creation
***Istanbul BFT** - a PBFT-inspired consensus algorithm with transaction finality, by AMIS.
***Peer Permissioning** - node/peer permissioning using smart contracts, ensuring only known parties can join the network
***Higher Performance** - Quorum offers significantly higher performance than public geth
**Monero** is a private, secure, untraceable, decentralised digital currency. You are your bank, you control your funds, and nobody can trace your transfers unless you allow them to do so.
**Privacy**: Monero uses a cryptographically sound system to allow you to send and receive funds without your transactions being easily revealed on the blockchain (the ledger of transactions that everyone has). This ensures that your purchases, receipts, and all transfers remain absolutely private by default.
**Security**: Using the power of a distributed peer-to-peer consensus network, every transaction on the network is cryptographically secured. Individual wallets have a 25 word mnemonic seed that is only displayed once, and can be written down to backup the wallet. Wallet files are encrypted with a passphrase to ensure they are useless if stolen.
**Untraceability**: By taking advantage of ring signatures, a special property of a certain type of cryptography, Monero is able to ensure that transactions are not only untraceable, but have an optional measure of ambiguity that ensures that transactions cannot easily be tied back to an individual user or computer.
- [Getmonero.org](https://getmonero.org) - The official Monero website
- [Lab.getmonero.org](https://lab.getmonero.org) - The official research group of Monero
- [RPC documentation](https://getmonero.org/resources/developer-guides/daemon-rpc.html) - RPC documentation of the Monero daemon
- [Wallet documentation](https://getmonero.org/resources/developer-guides/wallet-rpc.html) - Wallet documentation of the Monero daemon
- [Cryptonote Whitepaper](https://cryptonote.org/whitepaper.pdf) - White paper of cryptonote, the family of crypto-currencies of Monero
- [Review of the Cryptonote White Paper](https://downloads.getmonero.org/whitepaper_review.pdf) - By the research lab of Monero
- [Cryptonote Standards](https://cryptonote.org/cns) - The 10 Cryptonote standards (equivalent to BIPs for Bitcoin)
+ [**How to get started**](https://github.com/monero-project/monero#compiling-monero-from-source)
+ [**What is Monero? Most Comprehensive Guide**](https://blockgeeks.com/guides/monero/) / [Chinese version](https://github.com/liuchengxu/blockchain-tutorial/blob/master/content/monero/what-is-monero.md)
**IOTA** is a revolutionary new transactional settlement and data integrity layer for the Internet of Things. It’s based on a new distributed ledger architecture, the **Tangle**, which overcomes the inefficiencies of current **Blockchain** designs and introduces a new way of reaching consensus in a **decentralized peer-to-peer system**. For the first time ever, through IOTA people can transfer money without any fees. This means that even infinitesimally small nanopayments can be made through IOTA.
**IOTA** is the missing puzzle piece for **the Machine Economy** to fully emerge and reach its desired potential. We envision IOTA to be the public, permissionless backbone for the Internet of Things that enables true interoperability between all devices.
- [IOTA](https://iota.org) - Next Generation Blockchain
**EOSIO** is software that introduces a blockchain architecture designed to enable vertical and horizontal scaling of decentralized applications (the “EOSIO Software”). This is achieved through an operating system-like construct upon which applications can be built. The software provides accounts, authentication, databases, asynchronous communication and the scheduling of applications across multiple CPU cores and/or clusters. The resulting technology is a blockchain architecture that has the potential to scale to **millions of transactions per second**, eliminates user fees and allows for quick and easy deployment of decentralized applications. For more information, please read the[EOS.IO Technical White Paper](https://github.com/EOSIO/Documentation/blob/master/TechnicalWhitePaper.md).
**IPFS** ([the InterPlanetary File System](https://github.com/ipfs/faq/issues/76)) is a new hypermedia distribution protocol, addressed by content and identities. IPFS enables the creation of completely distributed applications. It aims to make the web faster, safer, and more open.
**IPFS** is a distributed file system that seeks to connect all computing devices with the same system of files. In some ways, this is similar to the original aims of the Web, but IPFS is actually more similar to a single bittorrent swarm exchanging git objects. You can read more about its origins in the paper [IPFS - Content Addressed, Versioned, P2P File System](https://github.com/ipfs/ipfs/blob/master/papers/ipfs-cap2pfs/ipfs-p2p-file-system.pdf?raw=true).
**IPFS** is becoming a new major subsystem of the internet. If built right, it could complement or replace HTTP. It could complement or replace even more. It sounds crazy. It _is_ crazy.
- [**Blockchain: from Digital Currency to Credit Society**](https://github.com/yjjnls/books/blob/master/block%20chain/%E5%8C%BA%E5%9D%97%E9%93%BE%20%E4%BB%8E%E6%95%B0%E5%AD%97%E8%B4%A7%E5%B8%81%E5%88%B0%E4%BF%A1%E7%94%A8%E7%A4%BE%E4%BC%9A.pdf)
- [**Attack of the 50 Foot Blockchain: Bitcoin, Blockchain, Ethereum & Smart Contracts**](https://davidgerard.co.uk/blockchain/table-of-contents/) by David Gerard, London, 2017 --
_What is a bitcoin? ++
The Bitcoin ideology ++
The incredible promises of Bitcoin! ++
Early Bitcoin: the rise to the first bubble ++
How Bitcoin mining centralised ++
Who is Satoshi Nakamoto? ++
Spending bitcoins in 2017 ++
Trading bitcoins in 2017: the second crypto bubble ++
Altcoins ++
Smart contracts, stupid humans ++
Business bafflegab, but on the Blockchain ++
Case study: Why you can’t put the music industry on a blockchain_
- [**IslandCoin White Paper - A Pen and Paper Cash System - How to Run a Blockchain on a Deserted Island**](https://github.com/bitsblocks/islandcoin-whitepaper)
- [**Permissioned Blockchains in Action**](https://www.manning.com/books/permissioned-blockchains-in-action) by Mansoor Ahmed-Rengers & Marta Piekarska-Geater, early access --
- [bankymoon](http://bankymoon.co.za/) - Blockchain consultancy. [Presented](http://goo.gl/L6vJBx) bitcoin-topped smart electricity meter. Once topped up, it chooses a plan, and starts moving energy.
- [Co-Tricity](https://co-tricity.com/) - Decentralised energy marketplace by [Innogy](https://innovationhub.innogy.com/) and [ConsenSys](https://consensys.net).
- [Electron](http://www.electron.org.uk/) - Reinventing energy on blockchain.
- [GridSingularity](http://gridsingularity.com) - Blockchain for Smart Grid. Declare three years of work on the technology.
- [lo3 energy](http://lo3energy.com) - Energy Services, Product Research & Development. Makers of [Brooklyn Microgrid](http://brooklynmicrogrid.com) along with [ConsenSys](https://consensys.net).
- [lumo](https://lumoenergy.com.au) - Energy provider. Experiment with blockchain.
- [PowerLedger](https://powerledger.io) - Decentralised energy marketpace.
- [PowerPeers](https://www.powerpeers.nl/) - Peer-to-peer energy marketplace in the Netherlands.
- [Solar Change](http://www.solarchange.co/) - Makers of [Solar Coin](http://solarcoin.org/). AltCoin for a MW of solar power.
- [Terraledger](https://terraledger.com) - Provider of Renewable Energy Certificates.
