The Slovak language is an Indo-European language that belongs to the West Slavic languages (together with Czech, Polish, Silesian, Kashubian, and Sorbian). The Czech and Slovak languages are mutually intelligible which means that even after the dissolution of Czechoslovakia Czech may be used in all official proceedings and documents in Slovakia (Minority Language Act 184/1999 Z. z., State Language Act 270/1995 Z. z.), and vice versa (Administration Procedure Act 500/2004 Sb.). However, Slovak is used in all official documents in Slovakia. Czech is only used a little bit. Slovak is spoken in Slovakia (by 5 million people), the United States (500,000), the CzechRepublic (320,000), Serbia (60,000), Ireland (30,000), Romania (22,000), Hungary (20,000), Poland (20,000), Canada (20,000), Croatia (5,000), Australia, Austria, Ukraine, and Bulgaria.

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