Quoting

Quotes are used when assigning values containing whitespace or special characters, to delimit variables, and to assign command output. They also improve readability by separating arguments from commands.

'...' remove the special meaning of enclosed characters except '
"..." remove the special meaning of enclosed characters except $, ', and \
\c remove the special meaning of character c
`command ` replace with the standard output of command

Get Korn Shell: Unix and Linux Programming Manual, Third Edition, The now with the O’Reilly learning platform.

O’Reilly members experience books, live events, courses curated by job role, and more from O’Reilly and nearly 200 top publishers.