Important people to the Jewish faith and explain why?

Aaron, brother of Moses and Miriam, and the first High Priest.

Abigail, a prophetess who became a wife of King David.

Abishai, one of King David's generals and relative.

Abner, cousin of King Saul and commander of his army, assassinated by Yoav.

Abraham, Isaac and Jacob, Judaism's "Three Patriarchs"