Last chance to find any errors
Proofreading* is the last stage in the editing process. Editors Canada defines it as “examining material after layout or in its final format to correct errors in textual and visual elements.”
Proofreading can be done on hard copy or PDF depending on your preference. I look for any copy editing errors that have snuck through, typographical and formatting errors, bad breaks, and page references, and ensure that design specifications have been followed.
*Many people use the terms “proofreading” and “copy editing” interchangeably, but they are two quite different processes done at different times during production (for a more-detailed answer, take a look at the FAQs or at my blog post). The big difference is that proofreading occurs after layout and looks at formatting as well as text.