Aulus Gellius was a Roman author and grammarian, who was probably born and certainly brought up in Rome. He was educated in Athens, after which he returned to Rome. He is famous for his Attic Nights, a commonplace book, or compilation of notes on grammar, philosophy, history, antiquarianism, and other subjects, preserving fragments of the works of many authors who might otherwise be unknown today.

Commonplace books are a way to compile knowledge, usually by writing information into books. They have been kept from antiquity, and were kept particularly during the Renaissance and in the nineteenth century. Such books are similar to scrapbooks filled with items of many kinds: notes, proverbs, adages, aphorisms, maxims, quotes, letters, poems, tables of weights and measures, prayers, legal formulas, and recipes.