Yes, it does take into account text that is hidden from view. This used to be (still is in some places) a deceptive tactic to rank a page higher in the search r

Yes, it does take into account text that is hidden from view. This used to be (still is in some places) a deceptive tactic to rank a page higher in the search results. You could hide a massive block of keywords out of site of your visitor, or hide links to sites that you want ranking higher. Alternatively, more malicious people would (and still do) hack into a website in order to hide links in this same manner. The website owner isn't likely to notice them if they aren't visible on a page. Google is pretty good at figuring out what is there for legitimate reasons versus spam.