Czech is a Western Slavonic language spoken by about 12 million people in the Czech Republic. There are also many people of Czech origin in other countries, particularly the USA. Czech is closely related to Slovak, Polish, and Sorbian. Many Czech speakers can be found especially in Austria (mostly in Vienna), Poland, Germany, Ukraine, Croatia (mostly in the Daruvar area), in Western Romania (in Banat), in Australia, and Canada.

Several tens of thousands of Czechs have continued to live in the Slovak Republic after the split of Czechoslovakia at the end of 1992. However, the largest group of Czech speakers outside the Czech Republic lives in the United States. According to the US Census, more than 90,000 Czech speakers lived in the United States in 1990.

Czech has been one of the languages of the European Parliament since 2004, when the Czech Republic joined the European Union.

Czech is one of the emerging languages for business in Europe. Czech is one of the languages occasionally translated by Comms Multilingual. Czech translation projects have included work on advertisements, brochures, instructions for mobile phones, commercial documents and typesetting.