server-side include <World-Wide Web> (SSI) The facility provided by most {web servers}, e.g. {NCSA httpd}, to replace special {tags} in an {HTML} file with the contents of another file before the file is sent out by the server, i.e. an {HTML} {macro}. NCSA httpd tutorial (http://hoohoo.ncsa.uiuc.edu/docs/tutorials/includes.html). (1996-09-08)