Megillat Esther:

A "Scroll of Esther" (Heb. מגילת אסתר, megilat ester) is a manuscript copy of the biblical Book of Esther, which recounts the story of the salvation of the Jews in the Persian Empire, read in synagogues on the Evening and Morning Services of the holiday of Purim. It is written on parchment by a Hebrew Scribe. 

The megillah itself tells us that Esther herself wrote the first megillah scroll: "Then Esther the queen, the daughter of Avihayil, and Mordechai the Jew, wrote with all emphasis to confirm this second letter of Purim" ( 9:29)