Yes, it's setting bits in a flag.
For example if setting text styles:
- bold = 1
- italic = 10
- underline = 100
I could combine the individual options into one value, by placing them
positionally in a binary number.
So 0b100 is underline, 0b110 is underline and italic, and 0b111 is all three options.
https://www.autohotkey.com/docs/commands/GuiControls.htm wrote:
1: Prevent unmodified keys
2: Prevent Shift-only keys
4: Prevent Ctrl-only keys
8: Prevent Alt-only keys
16: Prevent Shift+Ctrl keys
32: Prevent Shift+Alt keys
64: This value is not supported (it will not behave correctly)
128: Prevent Shift+Ctrl+Alt keys
in binary those numbers are:
0b1 (1)
0b10 (2)
0b100 (4)
0b1000 (8)
0b10000 (16)
0b100000 (32)
https://oeis.org/A000079 Sequence - Powers of 2
The reason binary representation is used is because each position or digit (On / Off) represents a composable option. E.g. I can combine any of the options listed from 1-128 which provides a range of numbers from 0-255.