Intermediate Guide

This guide is intended to help people with little or no Blockchain knowledge. If you have already contributed with Blockchain technologies before, you can skip to advanced guide.

This guide covers:

  1. Blockchain basics;
  2. Development concepts used by this project;
  3. Unit Testing;

Blockchain Basics

To contribute with this project, it's recommended that you have some basic knowledge about Blockchain and related technologies. Below is a list of what we consider the most basic knowledge in this area. Follow the links provided in this article to ensure you have a solid understanding about it. If you find any mistakes or unclear instruction, please contact the team or submit a pull request.

Block and BlockHeader

The blocks are used to store the data of the whole network, such as transactions or assets, and every block has it's own header to store meta-data about the block itself. A more detailed explanation can be found here.

Genesis block and the Blockchain

The blockchain is the logical structure, connecting Blocks in a one-way linked list, and every new block depends on it's previous block. The first block is called Genesis block. It's in this block that NEO and GAS is born. A more detailed explanation can be found here.

Cryptographic Hashing functions - SHA256 and RIPMED160

A hashing function can be applied to data resulting in a fixed size output. In NEO, we use 2 known algorithms to create hashes: SHA256 and RIPMED160. The first will result in a 256 bits (32 bytes) message, while the second will generate a 160 bits (20 bytes) message. In NEO, we use 32-byte hashes for computing Block and Transaction Hashes, and 20-bytes hashes for address generation. In code these types are represented in UInt256 and UInt160 respectively. A more detailed information can be found here.

Unspent Transaction Output (UTXO)

NEO uses the UTXO model, meaning that, to make a transaction, you must reference a transaction that you received in the past, that was not used yet. An address balance is the sum of all these 'unspent' transactions. A more detailed explanation can be found here.

Development concepts used by this project

This project relies on a few particular C# functionalities. A brief description can be found here.

← Basic GuideAdvanced Guide →