Triathlon is an sport that combines 3 sports: swimming, cycling, and running.
There are several types of Triathlon. This multisport event can be done individually or with team.
Duathlon is a combination of run-bike-run. Duathlon varies in length depending on the competitions.
Aquathlon is another type of variation of triathlon. It is combining running and swimming. Usually run/swim/run format is applied, rather than swim/run combination.
Winter triathlon is a perfect way for improving skills in multisport. It involves running, mountain biking, and cross-country skiing.
The standard distance (Olympic) in triathlon is the following: 15km swim, 40km bike, and 10km run.