How does Google treat hidden content which becomes visible when clicking a button?

Matt's answer:

Today’s question comes from Cologne. Thomas asks, “How does Google treat hidden content which becomes visible when clicking a button? Does it look spammy if most of the text is in such a section, for example, a simple page to buy something and Show Details button which reveals a lot of information about it?” OK. I wouldn’t be overly concerned about this. But let’s talk through the different consequences. It’s pretty common on the web for people to want to be able to say, OK, click here and then show manufacturer detail, show specification, show reviews. And that’s a pretty normal idiom at this point. It’s not deceptive. Nobody’s trying to be manipulative. It’s easy to see that this is text that’s intended for users. And so as long as you’re doing that, I really wouldn’t be too stressed out. Now certainly if you’re using a tiny little button that users can’t see and there’s like six pages of text buried in there and it’s not intended for users and it’s keyword stuffing, then that is something that we possibly could consider hidden text or probably would consider hidden text. But in general, if you just have something where you have a nice Ajax-y sort of site and things get revealed and you’re trying to keep things clean, that’s not the sort of thing that’s going to be on the top of our list to worry about because a lot of different sites really do that. It’s pretty common on the web. A lot of people expect that on the web. Take, for example, Wikipedia on your mobile phone, they’ll have different sections. And then if you click, they expand those sections. And there’s good usability reasons for doing that. So as long as you’re not trying to stuff something in in a hidden way that’s deceptive or trying to distort the rankings, as long as you’re just doing that for users, I think you’ll be in good shape.

by Matt Cutts - Google's Head of Search Quality Team

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