The answer is âmaybeâ. With respect to text, there are several sorts of PDFs (in my experience; Iâm no expert). One sort is just a text document which has been saved as a PDF; for those, you can highlight the text in the usual way (click and drag) â unless it has been âcopy protectedâ. If thatâs the issue, google around for possible ways to âunlockâ it. A second sort is comprised of images (i.e. just âphotographingâ the pages). For those, there is simply no text to be highlighted â itâs like trying to copy the text off a billboard in a photo. If thatâs the issue, perhaps you can manage some way to do OCR on the pages. A third sort is like the second, plus the image of the text has been somehow converted to a text stream, perhaps by some sort of OCR process, or simply by a person reading the text content of the image and keying it in. That text is then put on an âinvisibleâ layer which resides behind the image, overlapping the visible (but uncopyable) image of the text. This may seem silly, but it allows presentation of the document with its visible appearance being that of the original, while allowing copying (by making use of the content of the âinvisibleâ layer). This sort of PDF should allow click-drag copying, although the highlighted area may not align exactly with the visible text.
A PDF, in spite of the above, does not really present itself as text if you were to copy it from a CD, for example.