Editing layout’s modifiers table is another major function of
the Low level editor. The entire lower half of the Low level
window is dedicated to this task. Modifier keys do not produce
any characters themselves, but their combined state (on/off)
defines which (if any) characters are generated by character-
producing keys. KbdEdit supports four standard modifiers: SHIFT,
CTRL, ALT and the less known KANA modifier. Active vs. Unused
modifier combinations Combined state of all modifier keys
defines a modifier combination. As each modifier can have two
states (on/off), the total number of all possible combinations
is 2 ^ <number of modifiers>. For the most common case of 3
enabled modifiers (SHIFT, CTRL, ALT), there are 8 theoretically
possible combinations. Depending on a particular layout, not all
possible combinations are actually needed. For instance,
standard US English keyboard uses only 4 combinations (BASE,
SHIFT, CTRL and SHIFT+CTRL). ALT combinations are not used at
all, and most keys do not even have a