or — Logical or
or number [number] [number] [...]
or
number
...
The or command does a binary or of the numbers passed to it, so it can also be used as a logical or.
hecl> or 1 1 hecl> or 0 0 hecl> or 1 0 1 hecl> or 2 4 6 hecl> or 1 2 4 7