Do you actually say “MS?” I’ve only heard that as a prefix, like “MS DOS” or “MS Word,” but I’ve never heard someone say they work for “MS” or that “MS” makes X

Do you actually say “MS?” I’ve only heard that as a prefix, like “MS DOS” or “MS Word,” but I’ve never heard someone say they work for “MS” or that “MS” makes Xbox. I’ve also never heard “Big Blue” nor “Toshi.” I have heard “HN,” so got me there.