A FAQ is a list of frequently asked questions (FAQs) and answers on a particular topic (also known as Questions and Answers [Q&A] or Frequently Answered Questions). The format is often used in articles, websites, email lists, and online forums where common questions tend to recur, for example through posts or queries by new users related to common knowledge gaps. The purpose of an FAQ is generally to provide information on frequent questions or concerns; however, the format is a useful means of organizing information, and text consisting of questions and their answers may thus be called an FAQ regardless of whether the questions are actually frequently asked.

While the name may be recent, the FAQ format itself is quite old. For example, Matthew Hopkins wrote The Discovery of Witches in 1647 as a list of questions and answers, introduced as "Certain Queries answered". Many old catechisms are in a question-and-answer (Q&A) format. Summa Theologica, written by Thomas Aquinas in the second half of the 13th century, is a series of common questions about Christianity to which he wrote a series of replies. Plato's dialogues are even older.