Slovak is the official language of Slovakia where it is spoken by approximately 5.51 million people (2014). Slovak speakers are also found in the United States, the Czech Republic, Argentina, Serbia, Ireland, Romania, Poland, Canada, Hungary, Croatia, the United Kingdom, Australia, Austria, and Ukraine. Official transcriptions Slovak linguists do not usually use IPA for phonetic transcription of their own language or others, but have their own system based on the Slovak alphabet. Many English language textbooks make use of this alternative system of 'phonetic' transcription, a factor which probably contributes to some Slovaks developing a particular ('incorrect') pronunciation of certain English phonemes. In the following table, pronunciation of each grapheme is given in this system as well as in the IPA. Orthography Slovak uses the Latin script with small modifications that include the four diacritics (ˇ, ´, ¨, ˆ) placed above certain letters. The primary principle of Slovak spelling is the phonemic principle. The secondary principle is the morphological principle: forms derived from the same stem are written in the same way even if they are pronounced differently. An example of this principle is the assimilation rule (see below). The tertiary principle is the etymological principle, which can be seen in the use of i after certain consonants and of y after other consonants, although both i and y are pronounced the same way. Czech While most dialects of Czech and Slovak are mutually intelligible (see Comparison of Slovak and Czech), eastern Slovak dialects are less intelligible to speakers of Czech; they differ from Czech and from other Slovak dialects, and mutual contact between speakers of Czech and speakers of the eastern dialects is limited.