Rosetta Stone

The Rosetta Stone:

A black granite stone (granodiorite stele) from ancient Egyptian inscribed with a decree issued at Memphis in 196 BC on behalf of King Ptolemy V. The decree appears in three scripts: the upper text is Ancient Egyptian hieroglyphs, the middle portion Demotic script, and the lowest Ancient Greek. Because it presents essentially the same text in all three scripts (with some minor differences between them), it provided the key to the modern understanding of Egyptian hieroglyphs.

The Stone was discovered at Rosetta by the French expedition and surrendered to British troops in 1801. The Rosetta Stone is currently on permanent display at the British Museum, London.