JS floating message box with fade

(I'm not sure what is it call!) For example you enter a website, you see a the left there is开发者_如何学编程 a button with an arrow ( <- ), sroll with you, and when you click in a box expand, when you click agian the box close.

PLeas tell me what is it and where I can find some demo code :D Thanks

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I'm not sure what it's typically called, but I Googled around and eventually came up with: "side slide in hidden with jquery". It's a bit unwieldy, but it got results, and here's a jQuery plugin to do it. You might try some more searching to find something that could fit your needs better.

In addition, here's a jQuery plugin to keep elements on the page when you scroll, although I've seen better (Where they update more frequently. It's a tradeoff between browser load - with many javascript updates - and snappiness). Try Googling "scoll div with page jQuery" to find other results.