Hidden text is used by some webmasters to try and give search engines a lot more keywords. The idea is, that in the page code, although you can see the keywords, on the actual page – you can’t. It doesn’t often work as well as some people believe it does.
Common Methods that people use to try and hide the keywords on the page include:
Reducing the Text size to something like 1px high. This means that it can still be seen but looks a little odd (In as much as all you can see are the scribbles of 1px high words on the page.
Colouring the text to be the same colour as the page’s background. This is extremely amateurish. Not only does it involve the webmaster using zero brainpower to think of it (Just like reducing the text size), but it also requires a search engine’s zero processing power to detect it. This will get you caught (And quite frankly – too right!). If you are using hidden text, at least have some fun with it. Try new things…
Using CSS to hide it. CSS is wonderful. For the first time, it is possible to completely separate page style from content. There have been rumours of Google (And other Search Engines) now being able to render CSS – thus knowing what you are doing to hide the copy. That would take a LOT of processing power, and as a result, am not too sure… Anyway – With CSS you can hide the copy in many ways. Use the z-index command to sit it below any images you have on the page. using the display: none; syntax To hide it completely, or maybe you fancy using the position syntax to place it 10,000px to the left of the viewer’s screen…
Whatever way you do it. Hidden text is really a bit of a cop-out. It doesn’t require any brainpower to think of how to do it and is also really easily caught.
I suggest you not find any methods of spamming (If that is the route you wish to go down) because hidden text really is a waste of time. It will harm your website ranking and traffic.