Due to the large size of some elements which are repeated several times on the form (e.g. the pop-up language selection menu), JavaScript has been used to reduce the size of the page. In this manner the information need only be defined once but can re-appear in many places. The result is that the web page is dramatically smaller in size and much faster for you to download.
Some people choose to disable JavaScript in order to guard against potential security problems with maliciously-designed web pages. JavaScript is used in the previous page only to facilitate operation of the form. It is safe to enable JavaScript here, and also when visiting the rest of our web site.