"Yep" is an informal term used to express agreement or affirmation. It is often used in casual conversations as a simple way to say "yes." The word is commonly found in spoken language and text messages, making it a popular choice for quick responses. The term is part of a broader category of informal language that includes other variations like "yep," "yup," and "yeah." These expressions are typically used in friendly or relaxed settings, allowing speakers to convey their thoughts without the formality of standard language.