A “fork” is the term used to describe a single blockchain diverging into two paths. Generally this occurs as the result of a significant change in the network’s protocol that effectively splits the blockchain into an old way of doing things and a new way of doing things.

Forks can be categorized as hard forks or soft forks. Hard forks are the result of network changes that are so extensive that every node participating in the network must upgrade their software in order to be compatible with the new processes. A hard fork is a fundamental change in the way a blockchain operates, such that any nodes that do not upgrade their software are on a different blockchain altogether.

Soft forks, by contrast, are backwards-compatible. The rules of the network have been changed, but nodes running the old software will still be able to validate transactions. This is less dramatic than a hard fork.

The following is a comprehensive list of cryptocurrency forks.