The migrate module provides a flexible framework for migrating content into Drupal from other sources (e.g., when converting a web site from another CMS to Drupal). Out-of-the-box, support for creating core Drupal objects such as nodes, users, files, terms, and comments are included - it can easily be extended for migrating other kinds of content. Content is imported and rolled back using a bundled web interface (Migrate UI module) or included Drush commands (strongly recommended).
The focus in the migration space is on Drupal 8 - barring someone stepping in and taking over the Drupal 7 project, maintenance is at a bare minimum.
Support for contributed modules
The place to implement migration support for a contributed module is in that module, not in the Migrate module. That way, the migration support is always self-consistent with the current module implementation - it's not practical for the Migrate module to keep up with changes to all other contrib modules.
Historically, if this did not seem practical, or as an intermediate step before submitting it to the contrib module itself, support for some contrib modules has gone into the Migrate Extras module. We're now deprecating this module - every effort should be put into integrating migration support directly into the target module.
Specialized migration modules
These modules use the Migrate framework to implement imports from specific sources.
- The Economist
- Stanford Law School
- National September 11 Memorial & Museum
- E-Business Platform for Basel Tourism
- Lifeguard Press osCommerce
- Elle Decor Lookbook App for iPad
- Andrew Morten's (drewish) slides and video from a Drupalcon Denver session explaining the Migrate module in technical terms.
- Mike Ryan's slides and video from a Drupalcon Denver session explaining the migration process in non-technical terms.
- Migrating old HTML files into Drupal, by Four Kitchens
The Migrate module is primarily maintained by Mike Ryan of Virtuoso Performance.