IFS

Cited from Bash: Show IFS value

To show IFS value,
printf %q "$IFS"

What is the meaning of IFS=$'\n' in bash scripting?

Cited from Getting User Input Via Keyboard

cat -etv <<<"$IFS"

Sample outputs:
  ^I$

$

Where,

• $ - end of line i.e. newline 
• ^I$ - tab and newline