If you want to merge PDF files on a Mac, you might be tempted to use a tool like www.ilovepdf.com. Worse still, you might try and do it from Adobe’s Acrobat site and end up signing up to pay $200 or more per year for the privilege!
The good news is if you are on a Mac, you don’t need to do any of that.
Instead, open your PDF files using Preview. Make sure your view shows Thumbnails of the pages in each document. Then drag the thumbnail pages of one document into another. Then save the document you added the thumbnails to and you are done.
For example, let’s say you have two PDF files: abc.pdf and xyz.pdf. You want all the pages in abc.pdf to be in xyz.pdf. You open them both using Preview, you drag the thumbnails of abc.pdf over to the thumbnail section of xyz.pdf. Then you save xyz.pdf. (You can save abc.pdf as an empty document or quit and have it revert back to how it was.)
If you want to leave abc.pdf and xyz.pdf untouched but merge them into a third document, first copy xyz.pdf and give it a name like abcxyz.pdf. Then open abc and abcxyz.pdf using Preview. Then copy the thumbnails of abc.pdf into abcxyz.pdf and save abcxyz.pdf and quit and do not save abc.pdf. Now you have three files: abc.pdf and xyz.pdf are unchanged and abcxyz.pdf are merged copies of the two of them.
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