"Complicated" is a song by Canadian singer-songwriter Avril Lavigne, released in 2002 on her debut album "Let Go." Composed by Lavigne, alongside the Matrix production team members Lauren Christy, Graham Edwards, and Scott Spock, the track is typically performed in the key of F minor. It gained widespread popularity for its catchy pop-rock melody and relatable lyrics about the complexities of relationships. One interesting fact is that "Complicated" became a commercial success, topping the charts in several countries and earning Lavigne critical acclaim, launching her into international stardom at a young age. The melody features guitar-driven instrumentation and Lavigne's distinctive vocal delivery, showcasing her unique blend of punk and pop influences.