The suffix represents the stock exchange the stock is traded on. N represents the New York Stock Exchange and O represents the Nasdaq.
Sometimes a stock can be listed on more than one exchange so the suffix will give you an indication of which exchange the stock is on. For example the Australian company BHP Billiton Ltd is listed on multiple exchanges so is given a different suffix for the different exchanges (especially when the code is the same for each exchange). Below are a few examples of BHP:
BHP.AX - Australian Stock Exchange BHP.BA - Buenos Aires BHP.SG - Stuttgart BHP.F - Frankfurt BHP - NYSE BHP.DU - Dusseldorf
- BHP.AX - Australian Stock Exchange
- BHP.BA - Buenos Aires
- BHP.SG - Stuttgart
- BHP.F - Frankfurt
- BHP - NYSE
- BHP.DU - Dusseldorf