Two penny blue Two penny blue The Two Penny Blue or The Two Pence Blue was the world's second official postage stamp, produced in the United Kingdom of Great Britain and Ireland and issued after the Penny Black. Initial printing took place from 1 May 1840, and in all 6,460,000 were printed from two plates until 29 August. Officially the stamps were valid for postage from 6 May but were only available from 8 May. It was first sold to the public at the London Inland revenue office on 6 May 1840. Except for its denomination, the design is exactly the same as
Penny Black (research project) spammers. Using these methods to reduce spam will also require these policies to be universal amongst mail clients. Intended mass email may also not work as intended. For example, subscribers to a particular email service may end up getting their emails with a significant delay while the email service will also become an increased expenses to the provider. Penny Black (research project) The Penny Black Project is a Microsoft Research project that tries to find effective and practical ways of fighting spam. Because identifying spams consumes a recipient's time, the idea is to make the sender of emails "pay" a