#explain-card Due to the nature of blockchain technology, updates or changes on the chain must be agreed upon by all participating [[Node|nodes]]. If some nodes do not agree with the changes, the network splits into two, each following different sets of rules. A [[Soft fork|soft fork]] refers to a fork where old nodes can still participate in the network. It's like a compatible upgrade. The new rules are a subset of the old rules. Because of this, a soft fork is usually used to implement new features or improvements to the network. A well-known example of a soft fork in [[Bitcoin]] is Segregated Witness (SegWit).