The advantage of @-quoting is that escape sequences are not processed, which makes it easy to write, for example, a fully qualified file name:
@”c:\Docs\Source\a.txt” rather than “c:\\Docs\\Source\\a.txt”
To include a double quotation mark in an @-quoted string, double it:
@”””Ahoy!”” cried the captain.” -> “Ahoy!” cried the captain.