Apple's built-in Preview functions not simply as a PDF viewer like Adobe Reader, but additionally a PDF editor, this means it lets people to edit PDF files on Mac OS X 10.5 or later (Snow Leopard, Lion included). When you open a PDF file with Preview, click "Tools" on the top, then navigate to "Annotate", you can see "Add Text", "Add Note" "Highlight Text", "Add Link", "Underline Text" and "Strike Through Text" and so on.
These are the basic editing features that Preview offers. However it is insufficient. If you wish to edit native or scanned PDF files, as an example, customize the text, insert images or paragraphs on Mac, you'll need a stronger tool, say PDF Editor Pro for Mac. Besides enabling you to annotate, highlight, edit PDF files on Mac, it also permits you to insert text, images, rotate PDF files as smoothly as in a Microsoft Word. Just see how it works.
Part 1: Edit PDF Files on Mac
Step 1: Open PDF files with PDF Editor Pro for Mac. If your PDFs are scanned files, a pop up could remind you of selecting recognition language and performing OCR.
Step 2: When you open the PDF files with the PDF Editor, you are able to see the tool bar on the ribbon. These power tools listed in your local tool bar are generally used ones. Obviously, you may make your personal tool bar by clicking the "Customize" button.
Part 2: Annotate and Highlight PDF Files on Mac
Step 1: On the "Commenting Tools", you can see some Annotate icon. Select one of them to annotate PDF files on Mac as you like.
Step 2: Select and click Highlight icon 
you will find three ways to mark up the text, highlight, underline and strikethrough.
It is possible to scribble imprints within the PDF pages. All are on the toolbar or you can choose from Annotate menu.
After done the work for editing PDF on Mac, you can Save or Save As the PDF files. Free download it now to annotate, highlight, edit PDF files on Mac as you like.
Keys: add annotation to pdf files on mac, how to highlight pdf on mac
Related Guides: Insert Images Text to PDF Files on Mac
