What is a Fork?

A soft fork is implemented by copying and modifying the software code. The original project continues to exist, but a new project is created separately, developing in a different direction. Imagine the team behind your favorite cryptocurrency content website has a major disagreement on how to proceed. Part of the team might copy the site to another domain. Looking ahead, they may also publish articles different from the original content.

These projects are built on a common foundation and share the same historical data. It’s like a road splitting into two paths—their paths diverge from this point onward.

Note that such events often occur in open-source projects and have existed long before Bitcoin or Ethereum. However, only in the blockchain space is there a distinction between hard forks and soft forks. Below, we will discuss them in detail.

Hard Fork vs. Soft Fork

Despite their similar names and shared purpose, hard forks and soft forks are quite different. Let’s explore them in detail.

What is a Hard Fork?

A hard fork is a software upgrade that is not backward-compatible. Typically, this happens when nodes add new rules that conflict with the rules of older nodes. New nodes can only interact with other nodes running the updated software. As a result, the blockchain splits, creating two separate networks: one operating under the old rules and another under the new rules.

Thus, two networks now run in parallel. They will continue to produce blocks and transactions but no longer work on the same blockchain. Before the fork block, all nodes share the same blockchain (and the history remains intact), but afterward, they will have different blocks and transactions.

What is a Soft Fork?

A soft fork is a backward-compatible software upgrade. Upgraded nodes can still interact with non-upgraded nodes. A soft fork usually introduces a new rule that does not conflict with the old rules.

Hard Fork vs. Soft Fork: Which is Better?

Fundamentally, these two types of forks serve different purposes. A contentious hard fork can split a community in two, but a planned hard fork allows participants to freely choose whether to upgrade.

A soft fork is a smoother option. Generally, since the new upgrade does not conflict with previous rules, it only imposes certain restrictions. In other words, if the upgrade is implemented in a compatible way, there is no risk of network fragmentation.

Conclusion

Hard forks and soft forks are essential for the long-term success of blockchain networks. Despite the lack of a central authority, they enable changes and upgrades in a decentralized system.

Forks allow blockchains and cryptocurrencies to integrate new features during development. Without these mechanisms, we would need a centralized system with top-down control. Otherwise, we would be stuck with immutable rules throughout the software protocol’s lifecycle.