原文地址
什么是比特币分支（Bitcoin fork）？通俗的定义是指拥有共享历史的2个分别的块链版本。我们知道，块链是比特币等加密货币的基本单元，块链是基于开源软件协议的，而分支类似于软件升级更新，但还保留原来的块链历史和协议。分支可以是暂时的，也可以是永久的。
比特币分支的目的是为了增加比特币的容量，扩大比特币市场总体财富。逻辑上，分支是和股票配股增股一样的思维。因为现在比特币挖矿非常困难，比特币总体容量受限，为了拉更多的人入坑，除了炒高价格，还要增大容量，才能让人进来接盘。我认为，在开源和自由的表面下，比特币将越来越走向大鱼吃小鱼的机制，特别是从实行可分支开始。
原文链接：https://blog.coinbase.com/
抄录：
What is a Bitcoin fork?
David Farmer
There has been significant news coverage and developments in recent weeks about changes to digital currency networks. These are sometimes called “forks”. We wanted to provide a simple, non-technical explanation to add context to recent discussions (previous blog posts here and here).
What is a “fork”?
A “fork” is a change to the software of the digital currency that creates two separate versions of the blockchain with a shared history.
Forks can be temporary, lasting for a few minutes, or can be a permanent split in the network creating two separate versions of the blockchain. When this happens, two different digital currencies are also created.
Why are changes made to digital currency protocols like Bitcoin and Ethereum?
Coinbase currently supports 3 digital currencies — Bitcoin, Ethereum and Litecoin. Each of these digital currencies use open-source software protocols with independent development teams responsible for changes and improvements to the network, much in the same way that changes to internet protocols allow web browsing to become better over time.
Our mission is to create an open financial system for the world and we believe digital currencies will be fundamental in achieving this mission. However, many of these digital currencies are still in early development. Making improvements to the software — such as the number of transactions the network can support — is crucial to creating finance 2.0.
Why do forks happen?
There are a few reasons why a fork can happen. For example, when a change is proposed to a digital currency protocol, users need to show their support for the new version and upgrade — in a similar way to people regularly update applications on their computer. In order for these changes to get approved many people need to agree, just as changes to cellphone networks require many phone companies to agree.
What does this mean if I have digital currency stored on Coinbase?
Coinbase actively monitors protocol developments and works hard to ensure customer funds are safe in these events. Our policy is to support only one version of a digital currency. In order to determine which fork to support we look at factors such as size of the network, market value and customer demand. We make this decision carefully because safely supporting a new digital currency requires significant work for many teams.
