Duo, the green owl, is the well-known mascot of the language-learning platform Duolingo. He is a central figure in the Duolingo brand, embodying the company's playful and encouraging approach to learning.
Duo's primary role is to motivate users to engage with their language lessons. He is portrayed as a persistent and supportive cheerleader, celebrating users' successes and gently reminding them to practice. While he is known for his persistence, which has led to numerous internet memes about his "threatening" nature, the official brand guidelines state that Duo is not negative, angry, or aggressive. His notifications are meant to be encouraging, not menacing.
Duo does not speak but communicates through text in the app, push notifications, and emails. He is characterized as social, emotional, and "extra," with a personality that is expressive and playful.