IFS is a special shell variable in bash, ksh and POSIX shells that lets you configure how the shell splits words
by default it splits at spaces tabs and newlines
I use fish
a shell that is intentionally not POSIX compatible. While it borrows some principles from Bash and POSIX, it simplifies a lot of things and removes most footguns. Words are split at new lines in fish, which admittedly can also cause troubles, but not nearly as often as in bash and other POSIXy shells.
to make a good interactive shell