<!--#command argument="argument value"-->
command description
------- -----------
config sets time,size or error msg format
echo inserts the values of SSI variables into your
web page
exec executes a system command or a CGI and inserts
the output that command into a web page
flastmod inserts into your web page the last
time the file was modified
fsize inserts the size of the file
include inserts the contents of HTML files
into your web page