Picture orientation

The pictures in my post are showing up sideways on some devices but not all. When I previewed the post everything looked correct but they are showing up sideways on some computers, tablets and phones but not all. On my computer the pictures were the proper orientation but when I imported them into my media library they were rotated so I had to rotate them back to upright. It is not just a mac vs pc problem. Any advice would be helpful. Thank you.