Enclosing characters in double quotes (‘"’) preserves the literal value
of all characters within the quotes, with the exception of
‘$’, ‘`’, ‘\’,
and, when history expansion is enabled, ‘!’.
The characters ‘$’ and ‘`’
retain their special meaning within double quotes (see Shell Expansions).
The backslash retains its special meaning only when followed by one of
the following characters:
‘$’, ‘`’, ‘"’, ‘\’, or newline.
Within double quotes, backslashes that are followed by one of these
characters are removed. Backslashes preceding characters without a
special meaning are left unmodified.
A double quote may be quoted within double quotes by preceding it with
a backslash.
If enabled, history expansion will be performed unless an ‘!’
appearing in double quotes is escaped using a backslash.
The backslash preceding the ‘!’ is not removed.
The special parameters ‘*’ and ‘@’ have special meaning when in double quotes (see Shell Parameter Expansion).