Migration
Migration is the incremental upgrade of a piece of code.
It is often used for databases, for example, with Laravel database migrations; for components and frameworks, a framework migration: for example, CakePHP migration. Migration applies to versions, a version migration, within a framework, or between two distinct framework.
Usually, migration requires some action from the user, although a migration script may be provided.
Migration may also be called upgrades. They may be paired with a rollback, which allows to go back to the previous state, and try again later.