Show content from another of my files?

[google503]

I have made a file named menu.htm. It has html and css on it that makes up my navigation bar. I don't want to crowd my main page so is there a code which shows that content, just like <script src=whatever.js> but for html.

[Medyman]

Server side solution: http://www.dynamicdrive.com/forums/showthread.php?t=24540
Client side solution: http://www.dynamicdrive.com/forums/showthread.php?t=28620

[google503]

thanks