'Letters' in the Bible

Now Ahab had seventy sons in Samaria. And Jehu wrote letters, and sent to Samaria, unto the rulers of Jezreel, even the elders, and unto them that brought up the sons of Ahab, saying,

At that time Berodach-baladan the son of Baladan, king of Babylon, sent letters and a present unto Hezekiah; for he had heard that Hezekiah had been sick.