If you are unable to select or highlight specific text in a PDF document in Adobe Acrobat Reader on Windows, this post will help you fix it.

If you want to extract highlighted text from PDF file as a plain text file, then this post covers some good free PDF Highlight Extractor software to do that.

Removing text from a PDF isn't as easy as drawing a black bar across it. Fortunately, redaction tools let you truly erase sensitive text in Preview, Adobe Acrobat DC Pro, and PDFPen.

Apple makes adding comments, highlighting text, and adding a signature easy in macOS. Here's how to annotate a variety of files, from JPGs to PDFs, using macOS' integrated Preview.