Who is Vanar in Ramayana?

Excuse me, could you please clarify for me the identity of Vanar in the epic tale of Ramayana? I understand that it's a rich and complex narrative filled with many intriguing characters, but I'm particularly intrigued by the role and significance of Vanar within the story. Could you elaborate on his character, his relationship with the main protagonist Rama, and perhaps even his contributions to the overall narrative arc? Thank you in advance for shedding some light on this enigmatic figure.