In 1854, Sir Charles Wheatstone invented the cipher known as "Playfair," named ... pick a keyword and write it into a five-by-five square, omitting repeated letters and combining I and J in ...

Cipher continued to make progress at its Black Pearl site, nearing completion of the Phase 1 buildings, which cover more than 100,000 square feet. In addition, the Company continued discussions ...

Like the Playfair, the Double Playfair cipher uses 5x5 squares. In this case two keywords are chosen, and each square is filled in the same way as the Playfair. For keywords HAMBURG and NEWYORK ...