there are horizontal and vertical on my MacBook Air display
How to get rid of horizontal and vertical lines on my MacBook Air display
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Hello there.
Lines are on your screen are typically indicative of a hardware problem.
You most likely have already tried these, but just in case:
If these do not work, connect your laptop to an external monitor/display. If you're getting a clear picture here, chances are it's an internal problem with the display. Get your laptop serviced at an Apple Store or an Authorized Service Center.