The tax code allows you to match shares to your benefit so I cannot imagine why the FIFO and LIFO info is even posted.
FIFO - First In, First Out
First shares bought are matched with first shares sold.
LIFO - Last In, First Out
self-explanatory
FIFO and LIFO are used in determining inventory costs, but I have never seen them used in regards to stocks. Some folks could use them I guess.