The Minoans developed the first writing system in Europe around 1700 B.C.
The 3,000 clay tablets found at Knossos fall into two categories: a Minoan script called Linear A, and one used by Mycenaeans, who probably took over the palace in 1450 B.C., called Linear B. Linear A, still undeciphered, has 90 symbols that each stand for a syllable rather than a letter.
Additionally, some simple drawings serve as logograms, such as a picture of a cup instead of spelling it out. Linear B has been deciphered -it's an early form of Greek. What makes deciphering Linear A so hard is that scholars don't know what language the script records. The Linear B tablets noted the goods brought to the palace and to whom they were redistributed. The purposes of the linear A tablets were probably similar. The tablets were inscribed with a stylus, then left to dry.
They were temporary records, and could be submerged in water to erase their content. The fire that destroyed Knossos baked them.