[Questions] How can I find out about "print runs" or "reprints"? I see YouTubers use these terms, but how do they know?

Hi! I am kinda new to Pokemon collecting. I am trying to understand how print runs are determined? Where can I find information on this? I hear YouTubers talk about print runs and reprints. I think Shining Fates is an example of a theme that got another print run. I would assume that some only have one print run, while others that are more popular, have multiple print runs (therefore bringing down the value). I apologize if this has already been covered elsewhere. I did a Google search and found no information so I was hoping to get educated here. Thanks for your time!!!