My screen zoomed on me without warning. I cannot un-zoom it. The display is set at 1920x1080. I have a 21" iMac. Any suggestions?
Which mouse are you using? It sounds like you pinch zoomed, which is one of the numerous gestures used on a trackpad or magic mouse. Just pinch in with your thumb and forefinger.
If you're not using either one of those Apple devices, then post here. We'll have to figure out what happened.
Go to the system preferences and select universal access you will see options for zooming or use the key combinations as per the image below.
Hope this helps.
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