Keywords Online
http://www.allegrotechindexing.com/news011.htm

Brown, Fred
Allegro Time!
2001

Abstract:

Online indexes have the same logical structure as print indexes with main headings and usually subheadings. Some online indexes can also be searched electronically. A search request in Yahoo! returns a list of online category headings. Online indexes, like their print cousins, are true 'searchable structures,' not simply concordance lists of terms appearing in the text.