The Ei Engineering Index focuses on the literature in the field of engineering and does not include purely theoretical and sociological literature.
Ei Compendex Web is a merged Internet version of "Ei Compendex" and "Ei PageOne." The database adds 500,000 engineering documents each year. The data comes from 5,100 engineering journals, conference proceedings and technical reports, of which 2,600 are abstracts (Ei Compendex section). Since the 1990s, the database has added 2,500 new sources of literature.