The Masora is a set of notes that Jewish scholars wrote on the Hebrew Bible between about the sixth and the tenth centuries. The notes sit beside and around the holy text. They show how to read it: where the vowel sounds go (old Hebrew writing often did not mark them), how to chant the lines, and careful counts of letters, so a copyist would not change a word by accident. People who study the Bible still lean on this work; the standard Hebrew Bible text that grew from it is often called the Masoretic Text. You will almost only meet Masora in serious writing about the Bible or Hebrew, not in the street. Spellings wander a little — Masora, Masorah, and older Massorah all mean these notes.