My view on vi and vim (and nvi et al)

I have a confession: for all that I use it fairly often, I am a fairly basic user of vi. As such, I have a pretty unsophisticated view of what vi is; if I type 'vi' and something starts up that behaves like vi and is not too freakishly super-intelligent, I call it vi and don't think more about it, regardless of the name of the actual implementation. Unless I actively think about it, I'm only vaguely aware that there are at least two reimplementations of vi (vim and nvi), each with their own distinct additions to the original vi. I'm not generally conscious of any differences, and I'm certainly not sophisticated enough to notice any incompatibilities with 'classic vi' (which is still found on operating systems like Solaris 10).

Calling everything 'vi' is a bit sloppy of me, and no doubt confuses some people (and may irritate others). But it really is how I think about this; for my purposes, the advanced features of vim and nvi and so on are pretty much irrelevant, because all I ever use is a subset of basic vi.

(This is much the same way that I call /bin/sh 'the Bourne shell', regardless of which implementation it actually is, and I expect that all competent implementations will behave similarly enough that I can not care. If you force me to care, I will deduct points.)

Well, this isn't quite true. It turns out that there are two features of modern vi reimplementations that I really miss: multi-level undo and the ability to backspace back to a previous line. While I won't go much out of my way to get a version of vi that has them installed on a random machine (for instance, I certainly won't compile my own version), I will switch to using a version of vi that has those features if it's already there. But I still don't really pay attention to what version it is, and I still call all of them 'vi', despite this being technically incorrect.

(I actually don't know if anything but vim supports those two features.)

If I used vi intensively, this ignorance would be reasonably foolish; I could probably significantly improve things like editing code by learning the more advanced features of the vi family. But my vi usage is reasonably casual; I have other editors for more involved text editing, and most of my vi skills have basically been acquired through osmosis and other peculiar means.

(I believe that I learned a reasonable chunk of vi by going through the old BSD vi tutorial but in another editor, which sort of robbed the embedded editing exercises of their teaching power. Still, a reasonable amount of that has stuck with me, so it wasn't a total failure.)