First is an example without javascript

I know what you mean... but strictly speaking, this is not without Javascript. CGI::Ajax uses Javascript code (auto-generated and embedded in the page) to glue the server-side Perl routines to the client-side events.  Also, onkeyup="..." generally wouldn't work without Javascript enabled.

Although Ajax doesn't necessarily require Javascript, it always needs some dynamic/scripting environment client-side (alternatives to Javascript are for example VBScript or EGL).