It is a Spanish term which translates to 'The Classic' in English and is known in Catalan as El Classic. Matches involving Real Madrid and Barcelona - Spain's biggest and most successful clubs - are deemed to be the pinnacle of Spanish football, hence the idea that it is the country's 'classic' encounter.
A rivalry from the beginning\n\n In the middle of the 20th Century, the rivalry took on a new dimension. It was still known as a derby, rather than 'El Clsico' despite both teams being from different cities.