What purpose do the plugs on the back of my iMac serve? - Quora
21.5- and 27-inch iMacs (Mid 2011) | Macworld
Supercharge Yourself with the New Thunderbolt-Equipped Quad-Core iMac | B&H eXplora
Apple iMac 27" - Spring 2011 Reviews, Pros and Cons | TechSpot
Identify the ports on your Mac - Apple Support
20 Terms Every Mac User Should Know - Administrivia
Amazon.com: SABRENT Premium 3 Port Aluminum USB 3.0 Hub with Multi in 1 Card Reader (12" Cable) for iMac, All MacBooks, Mac Mini, or Any PC (HB-MACR) : Electronics
Apple iMac 21.5" All-in-One Desktop Computer i5-2500s 2.7GHz 8GB Ram 1TB Mac OS High Sierra MC812LL/A w/ Keyboard & Mouse
Amazon.com: SABRENT 4-Port USB 3.0 Hub for iMac Slim Uni-Body (HB-IMCU) : Electronics
Amazon.com: SABRENT 4-Port USB 3.0 Hub for iMac Slim Uni-Body (HB-IMCU) : Electronics
Mac USB Ports Stopped Working? It's Likely Easy to Fix | OSXDaily
Amazon.com: Mini DisplayPort to HDMI Adapter for iMac Mid 2011(27-inch, 21.5 inches) Mini DP (Thunderbolt) to HDMI Adapter Compatible with MacBook Air/Pro, Microsoft Surface Pro/Dock, Projector and More 1-Pack : Electronics
iMac Intel 21.5" EMC 2428 Teardown - iFixit
USB 3.0 for iMac mid 2011 | MacRumors Forums
Further Explained: Apple's iMac 2011 Model Hard Drive 'Restrictions'
Apple updates iMacs with Sandy Bridge processors, Thunderbolt ports, FaceTime HD camera and more - 9to5Mac