International Olympiads in Science and Mathematics are the world championships for school students held every year in a different country.
The most famous Olympiads are The International Mathematical Olympiad (IMO), The International Physics Olympiad (IPhO), The International Chemistry Olympiad (IChO), The International Biology Olympiad (IBO), The International Olympiad in Informatics (IOI) and The International Astronomy Olympiad (IAO).
Countries send a delegation of students and leaders to participate at the International level. India conducts National Olympiads to identify the best students who can represent India at the international level.