How close is the Czech and Slovak languages?
Both languages are very close to each other, and can be understood by both nations. But they are different languages, not what the first poster implied. There are characters in Czech language, such a hard r > ř that can be pronounced only by Czech natives. Slovaks or any other Slavic nation cannot pronounce it. Slovaks have own characters as well. Both nations can easily read each other articles, but the writing rules are different. Czechs have different writing style, and as other poster mentioned, the Slovakian language is softer. The vocabulary is similar, with occasional words not understood. Younger generation born after the dissolvent of Czechoslovakia are growing apart and having problems to understand each other.