A stock symbol, also called ticker symbol, is a particular set of letters assigned to a security for trading reasons. Stocks that are listed on the NYSE are limited to four letters or less. Securities that are listed on Nasdaq typically have four characters, but may have up to five letters. The fifth letter of a five-letter symbol contains company information. The fifth letter can sometimes be used to identify the type of stock or security: A or B stand for NASDAQ stocks' A and B class shares, respectively, while V or Y denote shares represented by American Depository Receipts (ADRs). There is no discernible difference between symbols with two letters, and those with three, four or even five letters because they are simply a shortcut for describing a company's stock.