Search engine indexing describes the process of reading a web page and extracting the content into a database. The term is usually used to describe if a page is in a SE database, i.e. if a page is indexed. The term "index" is used synonymously with database, i.e. a page is in the search engine index (database).
- It is very common for pages that have been indexed by a search engine to fall out of the database. Also called falling out of a search engine index.
- Search engines maintain multiple databases and will sometimes switch indexes (databases). If this happens your pages may temporarily (or preeminently) be taken out of the index.