What is an avatar? Try to define it. Then have a look at this possible definition given by Cambridge Dictionary.
Have you ever created one when playing on a computer game? Do you often change your profile picture on Twitter, WhatsApp or Facebook?
Related articles you can read about the issue:
What Do Our Online Avatars Reveal About Us? (The New York Times)
Could avatars help people who hear voices? (BBC News)
What does your profile picture say about you? - Quiz (The Guardian)