Wow! Okay, I finally heard the best explanation as to why Unix uses ls instead of list, or rm instead of remove.
In the past techies would say that these commands had short names because back in 1965 or so when all of this stuff was created, memory and disk were expensive and so they did everything to they could do to save space by shaving letters where they could.
But that didn’t answer questions for me like mount, umount, cpio, sleep, etc. My personal belief was that PhDs don’t really like typing and so why make the command longer if you don’t have to. So the commands were shortened just for speed. The designers never really saw Unix taking off like it did. Unix was written by PhDs for PhDs so what we might consider normal today wasn’t written for back in 1968. For example when you remove a file on Unix, it just does it; whereas on other operating systems it will ask you if you really want to remove it. After you say yes it will say “filename removed”. Unix doesn’t do that.
So why are these commands so short? Modems.
Yes, modems. Back in 1969 modems ran around a top speed of 150 baud. That is about 1000 times slower than internet access at home today. Imagine taking 30 minutes just to wait to see google’s home page. That’s what it would have been like back then if there were websites. Just a small picture would take 3 hours to see.
So common activities like moving files, deleting files, or duplicating files could be done faster if less data is traveling from the terminal to the server. These commands were done a lot. A lot more than most commands, and so to hasten data travel across slow modems copy, list, and remove were made cp, ls, and rm.