Ah, thanks, that's clear as day.Dalai wrote: Simple: they're flags that are either enabled or disabled, i.e. 1 or 0 - commonly called binary. If you rewrite a decimal number like 5 into binary it becomes 101 which means that two flags are enabled (1) and one is disabled (0). You can't use that same mechanism when using sequential decimal numbers because the flags would not be clear without ambiguity.
Dalai
And I stumbled on this useful page where the explanation is matching my dummy level
http://utceditors.totalcmd.net/tc_tools/ultra_tc_editors/df/english.xml