How do I "photorealistic"

When a texture says it is "photorealistic" does that mean the painter paid great attention to detail or that the a/c has actual textures somehow pulled from photos, and if so, what is the best way to go about this in PSP?
Flight Simulator and other chat
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https://forums.simviation.com/phpBB3/viewtopic.php?f=15&t=35288