Migration
In plain terms
A versioned, repeatable change to a database schema.
Going deeper
A migration scripts schema changes (adding tables/columns) so they apply consistently across environments and can be tracked. It version-controls the database structure.
Under the hood
Applied in order and often reversible; tools tie schema evolution to code commits.
Examples
Adding a column, Flyway/Liquibase, Rails/Django migrations, schema versioning.
Think of it like...
Like dated renovation blueprints applied in sequence to keep every site identical.