Things that can contribute to different display of websites on different computers.
By John Potter
Screen resolution is the number one contributor to a difference in display. Screen resolution is a setting on a computer that controls how many pixels are displayed vertically and horizontally. It’s kind of like the difference between a TV screen and a movie screen, but when you change the screen resolution on a computer websites generally don’t stretch. The content automatically gets rearranged to fit the new situation (See article: Ice, Liquid and Jello Design).
If you have a PC running windows you can adjust screen resolution by accessing your display properties in the control panel and then going to settings.
If you have a regular old monitor (shaped like your old TV, not your new wide screen HDTV) try to stick to the 4:3 aspect ratio resolutions: 320X240, 640X480, 1024X768, 1152X864, 1280X960, 1400X1050, 1600X1200 and 2048X1536. It will help keep images from getting stretched out.
Different browsers can also affect the way that websites display and different operating systems can display things somewhat differently. The resulting view is the combination of these things and possibly more factors. I, for instance, have four browsers installed and my computer can display five different screen resolutions. This means there are twenty different ways the web can appear to me based solely on these two factors. Consider that both Windows XP and Vista are popular as well as Mac's OS10 and that would be sixty ways the web could appear (assuming each had four browsers installed).
The bottom line is that unlike print, websites are designed to be displayed different ways. They are optimized for the user that is the primary target of the site, but compromises and calculated decisions are made to make it flexible as well.