A triathlon has three legs and usually follows the format of swim first, bike second and run last.
A duathlon encompasses two legs, ride and run. Usually set as run (longer distance), ride and run(shorter distance)
Aquathlon (Splash and Dash): Swim/Run
An aquathlon usually runs the format of run, swim and run again with the runs set at the same distance.
A Splash and Dash is usually swim then run.
An aquabike runs the format of a swim, then a ride and a (very) short run into the finish line.
Cross Tri (Off-Road Tri): Swim/Bike/Run
Same format as a triathlon (Swim/Bike/Run) but the bike is usually a mountain bike course and the run a cross country/off road course.
Superleague: 3 rounds, Swim/Bike/Run (1); Run/Bike/Swim (2); Bike/Swim/Run (3)
The superleague format is very new and currently still only available to select races. It consists of three short rounds which mix up the order in which they are competed.
Teams/Family Wave: Swim/Bike/Run
Teams - run as a traditional triathlon format but teams made up of two or three participants partake in a leg of the event each.
Family Wave - for kids races only where child may want a family member to complete the course with them for safety purposes.
Mixed Teams Relay - Swim/Bike/Run
A new format still only available for select races. Teams are made up of four participants (2 Boys, 2 Girls) with each participants doing a complete triathlon (Swim/Bike/Run) and then tagging their teammate. Participants race Girl-Boy-Girl-Boy.