Demonstratives are adjectives and pronouns that indicate which objects a sentence is referring to. English has four demonstratives: 'this', 'that', 'these', and 'those'.
Latin had several sets of demonstratives, including:
hic, haec, hoc ille, illa, illud iste, ista, istudThe second set, 'ille', etc., meaning 'that', developed into the definite articles in several Romance languages, such as 'el', 'la', 'los', 'las' in Spanish, and 'le', 'la', 'les' in French.