The default setting on most devices is to display black text on a white background. Setting your device to dark mode means that it will display white text on a dark background. Dark mode is intended to reduce blue light exposure and help with eye strain that comes with prolonged screen time.
While dark mode has a lot of benefits, it may not be better for your eyes. Using dark mode is helpful in that it's easier on the eyes than a stark, bright white screen. However, using a dark screen requires your pupils to dilate which can make it harder to focus on the screen.
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