For month after month, year after year, Lotus 1-2-3 was the best selling software program. If you ran a business, or if you had to keep track of finanaces, it was the first thing you put on your computer after DOS.
Lotus wasn't the first spreadsheet -- VisiCalc came first -- but it quickly became the most popular. It was relatively easy to use and by far the industry standard.
One interesting feature of Lotus was the slash key. Instead of pressing a function key* to activate what are now menu fuctions, you pressed slash to bring up the menu, and could use the arrow keys to move around.
The most annoying feature of Lotus -- at least, until it was fixed -- was that you could quit without saving your work. Slash and Q would get you right out of the program. And if you hadn't saved things first, they were gone. This probably caused as much cursing as any software invented. By version 3, you would get a warning, but before that, make sure you saved.
Also, Lotus didn't like to be on a hard drive. There was a strict copy protection scheme. First, you couldn't do it at all without cracking it. Then, they set up a system where you transferred Lotus from the disk, erasing it, as you copied it to the hard drive (this was common back in that era). But you still had to keep the original disk: Lotus would look for it on startup. If it wasn't in the A: drive, Lotus wouldn't run.
What happened to Lotus? Windows 3.1. They never got how it worked; the first versions of Lotus for Windows were still using keyboard controls instead of using the mouse. Microsoft also pushed Excel, and designed it so that Lotus users could easily adapt, including an automatic translator that would turn Lotus commands into Excel ones so you wouldn't lose effieciency while learning. Lotus took at long time to get their version 4 up and running on Windows.
They also wasted time with their integrated "Symphony" program, which was supposedly a word processor, spreadsheet, and database all in one. I think that integrated programs got the short shrift -- they probably would have worked just fine for most people's uses instead of a suite of features you don't use -- but Symphony was just a Lotus spreadsheet where you could type in text and have rudimentary word processing functions. It was even in the same file format (if you changed the extension)!
Lotus was eventually bought out by IBM, not for 1-2-3, which by then was dying, but for Lotus Notes, a nice bit of hypeware that was going to change the way we did business. Notes was both an e-mail client and a "database" -- a confusing use of the term, since it was nothing like a database. The Notes database was more like a message board. The idea was the people would collaborate on projects via computer. The idea is still "hot" in computing, but still hasn't caught on.
In any case, 1-2-3 is now part of Lotus Smartsuite, so it's really not dead, but Smartsuite isn't really all that popular. And compared to the way Lotus was all over back in the mid-80s, it's certainly taken a big fall.
*F1-F10 were used in the DOS days to activate what are now menu functions. F11 and F12 were added about the time Windows was replacing DOS and the function keys became obsolete. When was the last time you touched one?