CAPTCHAs: The struggle to tell real humans from fake. (theconversation.com)
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There have been multiple accounts created with the sole purpose of posting advertisement posts or replies containing unsolicited advertising.
Accounts which solely post advertisements, or persistently post them may be terminated.
The first modern barcode was scanned 50 years ago this summer – on a 10-pack of chewing gum in a grocery store in Troy, Ohio, in the U…S....
Most presolar grains were destroyed in the formation of the universe. But some survived on meteorites.