Identifying text constants and special characters in formulas
Use opening and closing quotation marks to indicate the beginning and end of text constants. Quotation marks without text between them indicate an empty value (no text).
Use backslashes to preserve special operator characters, such as double quotation marks or a carriage return character, simply as characters within a string (instead of as operators).
Example
 
"\"Fred " & "and Jane\"" returns “Fred and Jane”.
Related topics 
About formulas
Defining calculation fields
Text operators
Using operators in formulas
Functions reference (category list)
Functions reference (alphabetical list)