<human>:  Provide a list of the top 5 highest grossing movies of all time.
<bot>: 
1. Avatar (2009) – 2.78 billion
2. Titanic (1997) – 2.18 billion
3. Avengers: Endgame (2019) – 2.79 billion
4. Star Wars: Episode VII – The Force Awakens (2015) – 2.07 billion
5. Avengers: Infinity War (2018) – 2.05 billion