I strongly recommend the book Unix Power Tools for all such questions. Quotes become easier to grok once you think of different ways to remove meaning of speci

I strongly recommend the book Unix Power Tools for all such questions. Quotes become easier to grok once you think of different ways to remove meaning of special characters. Basically, 1) backslash removes special meaning of the next character, 2) surrounding by double quote removes special meaning of all characters except backslash, dollar, and backtick, and 3) surrounding by single quotes removes all special meanings.