There's only one operating system where what Shadok says in comments to another answer is actually the case. It isn't even a Unix. Guess which operating system is the one whose more command(s) only give(s) you the Unix user experience of 1988.
On Solaris:
You have two choices of more command: /usr/bin/more and /usr/xpg4/bin/more. The former doesn't have a back one line command. But the latter does. It is k, optionally prefixed by a number to indicate a different number of lines. The xpg4 in the directory name references the X/Open Portability Guide Issue 4, a 1992 standard for Unices that preceded the Single Unix Specification.
Further reading
On FreeBSD and MacOS 10:
/usr/bin/more and /usr/bin/less are links to the same file, which is GNU less. Invoked via more it tries to follow the POSIX/SUS specification for more. The Single Unix Specification specifies that the command for scrolling back one (or more) lines is k, optionally prefixed by a number to indicate a different number of lines, just like Solaris.
Further reading
- more(1). FreeBSD man pages. 2009.
- more. The Open Group Base Specifications Issue 6. 2004.
- more(1). MacOS 10 manual pages. 2008.
On Linux:
The more command is the BSD more version 5.19, from 1988. It doesn't have a key sequence for going backwards by a line, only one for going backwards by a screenful.
Further reading