Strange graphics showing up all over ...

What are these suppose to mean ?

I've been seeing them all over.  For example here.

Tags

1. question
2. graphis
3. bar codes

Comments

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Mark de LA says
Here is a generator: http://qrcode.kaywa.com/
The one for http://www.fastblogit.com looks like this:

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C says

I think it is some kind of checksum related to SHA1 in a 2D barcode.

See: http://superuser.com/questions/146511/what-are-these-google-sha1-images 

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C says

Wikipedia has a pic down at the bottom of: http://en.wikipedia.org/wiki/Barcode

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Seth says

ok, that's it.   But how do we use these?  What it the practical reason to publish these graphics on the web?   Is there some app that scans that and goes there?

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See Also

1. Thought Question from WE THE PEOPLE with 1 viewings related by tag "question".
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