A writ of habeas corpus is a legal order that requires a person holding someone in custody to bring the detainee before a court. This writ is a fundamental protection against unlawful detention, ensuring that individuals can challenge the legality of their imprisonment. It is often referred to as the "great writ" because it safeguards personal freedom. The term "habeas corpus" comes from Latin, meaning "you shall have the body." This legal principle is rooted in the Magna Carta of 1215 and is a key component of many legal systems, including those in the United States and United Kingdom.