If I remember correctly, vi was the visual mode of ex. I am trying to find some references for this. Here's one I could find from <https://pubs.opengroup.org/

If I remember correctly, vi was the visual mode of ex. I am trying to find some references for this. Here's one I could find from <https://pubs.opengroup.org/onlinepubs/9699919799/utilities/vi.html https://pubs.opengroup.org/onlinepubs/9699919799/utilities/v...>: > While ex and vi have historically been implemented as a single utility, this is not required by POSIX.1-2017. Better references would be very welcome. By the way, we can see this even today. For example, first type the following command in your terminal: ex Then at the ex prompt (the colon prompt), type this: vi This should bring up full blown Vim. The reverse is possible too. For example, in Vim, type: Q This takes us to Ex mode. Then in Ex mode type: vi This brings back Vim again.