A network upgrade refers to changes made to the underlying protocol of a blockchain. These upgrades can improve performance, enhance security, or introduce new features.Upgrades may consist of soft forks or hard forks. A soft fork allows for backward compatibility, meaning that only some nodes need to upgrade, while the rest can still function on the older version. A hard fork, on the other hand, results in a split where two separate blockchains emerge, often due to disagreements within the community.Reasons for network upgrades include fixing bugs, increasing transaction speeds, or changing consensus mechanisms. For instance, a cryptocurrency might shift from proof-of-work to proof-of-stake to reduce energy consumption.Before an upgrade is implemented, extensive discussions and testing usually take place to ensure that it benefits the community. Successful upgrades can lead to increased adoption and trust, while failed or controversial upgrades may result in division or loss of value.