What does this symbol on a guitar tab stand for?!

Question: I am just learning how to play electric guitar and I can play a couple songs, but what does the symbol "x" stand for on a tab. An example is at the link below:

http://i75.photobucket.com/albums/i291/n...

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Answers: I am just learning how to play electric guitar and I can play a couple songs, but what does the symbol "x" stand for on a tab. An example is at the link below:

http://i75.photobucket.com/albums/i291/n...

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it stands for dont play the note

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