Portuguese language is one of the Romance languages. Like all other languages of the group, Portuguese is a direct modern descendant of Latin, the vernacular Latin of the Roman soldier and colonist rather than the classical Latin of the cultured Roman citizen. It developed in ancient Gallaeci (modern Galicia, in north western Spain) and in northern Portugal and then spread throughout present-day Portugal. Portuguese owes its importance (as the second Romance language, after Spanish, in terms of numbers of speakers) largely to its position as the language of Brazil, where more than 150 million people speak it. In Portugal itself there are about 10 million speakers. It is estimated that there are also some 4,6 million Portuguese speakers in Africa (some of whom also use creole) and about 500,000 in the United States. There are five main Portuguese dialect groups, all mutually intelligible: (1) Northern, or Galician, (2) Central, or Beira, (3) Southern (including Lisbon, Alentejo and Algarve), (4) Insular (including the dialects of Madeira and the Azores and (5) Brazilian. Typical of the Portuguese sound system is the use of nasal vowels, indicated in the orthography by m or n following the vowel (e.g., sim "yes", bem "well") or by the use of a tilde (~) over the vowel ( mão "hand", nação "nation").