Display capabilities

In the past (until the 90's) customers outside the United States and Europe often had less capable computer systems than those in the U.S. It was common for other countries to lag two to three years behind in getting the latest in personal computer technology. This gap has significantly decreased in recent years.

Similarly, in older text mode operating systems it was common for the number of lines of text on the screen to vary. For instance while most U.S. and European systems allowed 25 lines of text on the screen, some Japanese systems had fewer, because the display height of Japanese characters is greater (to allow better differentiation given the complexity of the characters) and some systems reserved one or two lines for a "Front End Processor" (the equivalent of today's Input Method Editor). Variations also existed between various vendors' hardware in Japan until a standard system emerged.

Today there is less need to make special allowances for hardware limitations in other countries for desktop displays - BUT many similar considerations SHOULD be kept in mind for the following reasons:

1. Accessibility. For instance, the fact that virtually every monitor sold today can support millions of colors doesn't make it possible for color blind users to distinguish all colors. For more guidance in this area, check out the W3C Web Accessibility Initiative.
2. Although a screen resolution of 1024 x 768 is predominant in the US, Europe, and Japan, in some areas, such as South East Asia, smaller screen sizes such as 800 x 600 may still be common. Flexible design approaches help significantly in addressing such differences these days. On the other hand, there are also a lot of other devices (PDAs, cellphones,...) with much more restrictive screens. Although not all Web pages may need to work on cellphones, try to design with as few limitations as possible.
3. Characters in other scripts may still take up more room vertically and horizontally. Although screen real estate tends to be more flexible these days, you should still allow for greater line heights, character complexity, and inter-line spacing where necessary.

So, even though hardware variations across locales are not much of an issue now, the same sort of measures are often still needed, though for different reasons.