Here's why:
* Bilingual means being able to speak, read, and write in two languages fluently. It doesn't matter if those languages are official languages of a country or region.
* Official language refers to a language recognized by a government for use in official functions like government documents, legal proceedings, and education.
Example:
* A person who speaks English and Spanish is bilingual, even if neither language is an official language in their country.
* A country might have two official languages, but a citizen could be bilingual in a different combination of languages.
Therefore, being bilingual is about individual proficiency in two languages, while official languages are about government recognition and usage.