What are the names of the ports I have in my Macbook Pro to plug an external monitor into?

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It would be Mini-DVI, Mini DisplayPort or Thunderbolt, depending on the MacBook Pro model you have. Open  > About this Mac > More Info, and tell us the model identifier of your MacBook, or if you have Mountain Lion, it will tell you which MacBook Pro you have

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You have Thunderbolt or Mini DisplayPort. If you know which external display you want or you already have it, look at the ports it has got and get a Mini DisplayPort adapter for it. There are Mini DisplayPort adapters for DVI, VGA and HDMI.

Most external displays have DVI, VGA or HDMI. If you can use HDMI, use it, because it will provide much better quality. See > http://support.apple.com/kb/HT4241?viewlocale=en_US&locale=en_US

Mini DisplayPort adapters can be used with Thunderbolt

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