There are lots of free ways to view PDF’s, including Adobe Reader and Apple Preview (on the Mac). Adobe Acrobat is licensed software that is overpowered for just reading PDF’s.
There’s often confusion about the difference between Adobe Reader and Adobe Acrobat. Reader is a PDF viewer, which allows you to read PDF’s on your screen, fill out PDF forms on your computer (assuming that feature has been built into the PDF), and print out PDF’s. Acrobat goes much further, and is really a tool for creating PDF’s.
Our Adobe Acrobat license allows a limited number of people to use the software concurrently. On the other hand, anyone can use Adobe Reader and Apple Preview for free. If you use Acrobat when you don’t really need all that power, you may be blocking out someone who needs the full-featured product.
If Acrobat asks you, do not allow it to be the default, and indicate that you don’t want to be asked about it again. Then, if you really need it in a specific situation, open Acrobat directly from your Start Menu or Application folder.