Hard Fork
A major change to a blockchain protocol that is not backward-compatible. Nodes that do not upgrade to the new rules are rejected by the new chain, sometimes creating two separate blockchains. Bitcoin Cash was created via a hard fork of Bitcoin.
Why It Matters
A hard fork occurs when a cryptocurrency’s code is altered, resulting in the creation of a new version of the blockchain. This matters because it can affect the currency’s functionality and value, and can create controversy within the community.
Example
For instance, Bitcoin Cash was created from a hard fork of Bitcoin in 2017, aiming to increase transaction speed and block size. Users must decide which version to support in the wake of such changes.
Beginner Context
If you’re new to crypto, understanding hard forks can help you stay informed about potential splits in currencies you invest in, as they can affect your holdings significantly.
Mike Starr
Founder, CryptoWizardTools · M.S. Organizational Management
Last reviewed: August 2026
Related Terms
Bearish
A negative outlook on the price direction of a cryptocurrency or the broader market. A bearish investor expects prices to decline. The opposite of bullish.
Peer-to-Peer
A decentralized network where participants interact directly with each other without intermediaries.
FOMO
Fear Of Missing Out. The anxiety that an exciting opportunity is being missed, often leading to impulsive investment decisions based on hype rather than analysis.
Cold Wallet
A cryptocurrency wallet that is not connected to the internet, providing enhanced security against hacking. Examples include hardware wallets and paper wallets.
Layer 1
The base blockchain protocol (e.g., Bitcoin, Ethereum, Solana). Layer 1 solutions focus on improving the underlying blockchain itself.