捷克语（čeština）属于斯拉夫语族西斯拉夫语支的成员，属同一语支的语言还有斯洛伐克语、波兰语、波美拉尼亚语、索布语、西里西亚语等语言。捷克语的语言人口有1200万人，他们大多数都居住于捷克共和国。捷克语有42个字母，含二合的"ch"。方言以波希米亚、中摩拉维亚（哈纳）、西里西亚（莱赫）、东摩拉维亚四大方言为主。捷克共和国目前有人口1000万，此外，世界各地大约还生活着100万捷克人，其中有20至30万人使用捷克语。

很多人都认为捷克语是一种非常难学的语言。其中一个原因，是捷克语丰富的语态。据统计，捷克语的形态多达超过200种，这些不同的形态，使句子内的词语可以任意自由组合，而不用担心语序的问题。一方面，这是斯拉夫语的特色；但另一方面，这语言上的自由，亦对这些语言的学习者造成困难。

Czech (/ˈtʃɛk/; čeština Czech pronunciation:[ˈt͡ʃɛʃcɪna]), formerly known as Bohemian (/boʊˈhiːmiən, bə-/; lingua Bohemica in Latin), is a West Slavic language strongly influenced by Latin and German language, spoken by over 10 million people and it is the official language of the Czech Republic. Czech's closest relative is Slovak, with which it is mutually intelligible. It is closely related to other West Slavic languages, such as Silesian and Polish. Although most Czech vocabulary is based on shared roots with Slavic, Romance, and Germanic languages, many loanwords (most associated with high culture) have been adopted in recent years.