Wait, are you just now getting that web pages sometimes have invisible text on them? It’s fairly common, and (I thought) pretty well known.
Here’s some right now!
I recall it being used once in a while on the SDMB. This thread is a good example.
My word, it’s everywhere!
The way to see the invisible text is to select it, thus highlighting the text against the select box background. I use invisible text on practically every blog post, to ‘help’ the search engines and Adsense. If I put a bunch of invisible text about an animal in this post, the ads will see it, and reflect the ‘content’.
Raccoons in the dark, finding other raccoons. Look at all the raccoons.
No, the question (since answered) was why do job ads have seemingly unrelated hidden text.
Doesn’t seem to be working. 