Soft Fork

It is a protocol upgrade where only the previously valid transactions are made invalid, where most of the soft forks require the miners to upgrade to their mining software. This means that soft forks refer to the changes applied to a blockchain for adding or modifying any functionality devoid of causing any fundamental structural change. The crypto soft forks do not require all the miners on the network to agree to run the new code as it can be implemented with the majority of the miners agreeing on it.