Macbook pro dual screens

Up until about 10.9, Macs could run 2 screens as an Extended Desktop, sharing an edge that you specified. You can still use them that way. It looks like this:

Mission Control allows you to specify 'Displays have separate Spaces', and you can use them independently and tie them to different groups of Applications:

OS X: Using multiple displays in Mavericks - Apple Support

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Yes, that is dual display

Dual display and video mirroring: Simultaneously supports full native resolution on the built-in display and up to 2560 by 1600 pixels on an external display, both at millions of colors

MacBook Pro (15-inch, Late 2011) - Technical Specifications

http://www.everymac.com/systems/apple/macbook_pro/specs/macbook-pro-core-i5-2.4- 13-late-2011-unibody-thunderbolt-specs.html

BTW, this is the Mac Pro desktop forum