Penny Blue Penny Blue The Penny Blue is frequently mistaken for a postage stamp of Britain. It is from a series of proof impressions which were made at the time Rowland Hill was looking at the new colours which were to be used for the stamps which were to replace the Penny Black and the original 1840 issue of the Two pence Blue. The decision to change the black stamp to red had already been made, and at the same time the colour of the ink used for the cancellations was to be changed from red to black. Although it had been
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