With five separate modifiers, there are up to 32 possible modifier key combinations, which should be more than sufficient for most uses. The question is how to decide on which modifier combinations are needed. The answer to that is dependent on many things, but here are some guidelines: • If you are dealing with a Roman alphabet or other script with upper and lower case, then you should probably make shift produce upper case, and no shift produce lower case. • Very often, shift and caps lock will be the same for letter keys. They do not need to be the same for non-letter keys (numbers and punctuation). • It is often a good idea to have the command-key combinations either the same as without a command key, or the same as what is printed on the keys. This helps in making the keyboard shortcuts work as expected. • One approach in having two scripts (e.g. Devanagari and Roman) available is to use caps lock to switch between the two scripts. • The most commonly used characters should require fewer modifier keys. • The control key is not always useful, as its interpretation can be over-ridden by the operating system. For example, control-i may well be seen as a tab, and some control-key combinations may simply do nothing. Next page Up to "Modifier keys"