This is also called as Verbatim String Literals
By prefixing a string literal with "@", you can insert line breaks and other special characters into a string, and the CSharp compiler will interpret everything between the open and closing quotation marks as the contents of that string. Note that quotation marks within the string need to be doubled, or else the compiler will assume it has hit the end of the string literal.
1. To include a double quotation mark in an @-quoted string
// "Ahoy!" cried the captain.
string comment = @"""Ahoy!"" cried the captain."
2. To skip escape sequence
// rather than "c:\\Docs\\Source\\a.txt"
string path = @"c:\Docs\Source\a.txt"
3. To include html string
string script = @"";