Sequence of loading the site

[BobB]

I use several different computers to access this site. It seems that as the site is loading, the page forms differently depending upon the computer. Some of them are running XP pro, some XP home and one of them Windows 7 pro. All have different BIOS programmes.

What programme defines how the page loads ? I suppose it could also be the server sending the information.

[EtchedPixels]

Web browser

(Plus the order the bits arrive will affect how it appears bit by bit but not final layout)