Latin was originally spoken in Latium, in the Italian Peninsula. Through the power of the Roman Republic, it became the dominant language, initially in Italy and subsequently throughout the Roman Empire. Vulgar Latin developed into the Romance languages, such as Italian, Portuguese, Spanish, French, and Romanian. Latin, Greek and French have contributed many words to the English language. Latin and Ancient Greek roots are used in theology, biology, and medicine.
By the late Roman Republic (75 BC), Old Latin had been standardised into Classical Latin. Vulgar Latin was the colloquial form spoken during the same time and attested in inscriptions and the works of comic playwrights like Plautus and Terence. Late Latin is the written language from the 3rd century, and Medieval Latin the language used from the 9th century to the Renaissance which used Renaissance Latin. Later, Early Modern Latin and Modern Latin evolved. Latin was used as the language of international communication, scholarship, and science until well into the 18th century, when it began to be supplanted by vernaculars. Ecclesiastical Latin remains the official language of the Holy See and the Roman Rite of the Catholic Church.
Latin is a highly inflected language, with three distinct genders, seven noun cases, four verb conjugations, four verb principal parts, six tenses, three persons, three moods, two voices, two aspects and two numbers.
A number of historical phases of the language have been recognised, each distinguished by subtle differences in vocabulary, usage, spelling, morphology, and syntax. There are no hard and fast rules of classification; different scholars emphasise different features. As a result, the list has variants, as well as alternative names. In addition to the historical phases, Ecclesiastical Latin refers to the styles used by the writers of the Roman Catholic Church as well as by Protestant scholars from Late Antiquity onward.