> How does one embed e.g. code easily in the document?

You don't. For APIs and such, documentation is published online, and you don't need Word for that. Word is used in some industries, where printed manual is needed.

What about the printed manuals? I think they still have some of those not too long ago (e.g. Intel manuals). What was the tool chosen? Very curious to know.

Or, maybe a legacy example -- how were the printed manuals of Microsoft C 6.0 written? That was in the early 90s I think.

Framemaker.

Thanks, thought MSFT was using its own tools.

If you don't make it, you can't use it.

Microsoft has never made a technical publishing package, so it has to be outsourced.

Yeah I agreed. Kinda missed the old days with thick manuals. I bought one for gdb a couple of years ago and love it -- despite it is just the paper version of the online one.