Mona Vanderwaal is a fictional character from the television series Pretty Little Liars. She is known for her intelligence and resourcefulness, often using her skills in technology and strategy to navigate complex situations. Initially introduced as a shy and socially awkward girl, Mona evolves throughout the series, revealing her multifaceted personality. In the show, Mona becomes a key player in the mystery surrounding the identity of A, the main antagonist. Her character experiences significant development, including moments of friendship and betrayal, making her one of the more complex figures in the series.