Wow....

1989 - Conception
1990 - "WorldWideWeb" browser/editor, server
1991 - Justification
1992 - Persuasion
1993 - Proliferation
1994 - WWW1, WWW2, W3C.
1996,7 - PNG, PICS, HTTP 1.1, HTML 3.2, 4.0, CSS,
1998,9 - XML, RDF, P3P, CSS2, IPR?, HTTP-NG, ...