Novak Djokovic, the current men's singles world No. 1.. The Pepperstone ATP rankings are the Association of Tennis Professionals' (ATP) merit-based system for determining the rankings in men's tennis.The top-ranked player is the player who, over the previous 52 weeks, has garnered the most ranking points on the ATP Tour.Points are awarded based on how far a player advances in tournaments and ...
https://en.wikipedia.org/wiki/List_of_ATP_number_1_ranked_singles_tennis_players