The Fields Medal is a prize awarded to two, three, or four mathematicians under 40 years of age at the International Congress of the International Mathematical Union (IMU), a meeting that takes place every four years.

The Fields Medal is widely regarded as the highest honor a mathematician can receive, and has been described by many as the mathematician's "Nobel Prize". According to Academic Excellence Survey by ARWU, Fields Medal is the top award in the field of mathematics worldwide, and in another reputation survey conducted by IREG in 2013-14, Fields Medal came closely after Abel Prize as the second most prestigious international award in mathematics.

The prize comes with a monetary award, which since 2006 has been $15,000 CAD. The colloquial name is in honour of Canadian mathematician John Charles Fields. Fields was instrumental in establishing the award, designing the medal itself, and funding the monetary component.

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