What is this image that Google code provides?

Google Code provides a barcode like this:

When开发者_运维知识库 you download software. What is its purpose (I assume it is related to the SHA1 checksum, but if so, how is it used)?

Edit: Now that I know its name, I found this article. Thanks!

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This is a QR code, frequently used for entering URLs into mobile phones. It can be helpful if someone posts software that could be installed, say, on an Android phone; instead of manually entering the URL on the phone keyboard, you can just use an app like Barcode Scanner from the open source ZXing project to easily scan it in.

If you're not trying to download something directly onto your phone, it's probably not all that useful.

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It's a QR code and encodes a small amount of data - typically a URL. You can scan them for example using a phone and then visit the URL.

[Update: it's a URL for downloading msysGit.]

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It's a 2-Dimensional Barcode. There's software out there that can scan it.