The largest group is the ethnic Vietnamese ( Kinh ), who comprise over 85 percent of the population.
The country is largely lush and tropical, though the temperature in the northern mountains can cool to near freezing in the winter and the central regions often experience droughts. The current population is approximately seventy-seven million composed almost exclusively of indigenous peoples.The country's birth rate, estimated to increase at 1.37 percent per year, has led to rapid population growth since the 1980s with approximately 34 percent of the population under 14 years of age. Vietnamese is the dominant language, spoken by an estimated 86.7 percent of the population.It is a tonal Mon-Khmer language with strong Chinese lexical influences.As the official language, Vietnamese is taught in schools throughout the country.Since the 1940s, Vietnamese governments have made great progress in raising literacy rates and approximately 90 percent of the adult population is literate.Its 2,135 miles (3,444 kilometers) of coastline run from its border with Cambodia on the Gulf of Thailand along the South China Sea to its border with China.The delineation of Vietnam's borders has been a focus of dispute in the post–1975 period, notably the ownership disputes with China, Malaysia, the Philippines, Taiwan, and Malaysia over the Spratly Islands; and with China and Taiwan over the Paracel Islands.The Chinese objected to this new name because it was the same as an ancient state that had rebelled against Chinese rule. Vietnamese officials resented the change and it did not attain public acceptance until the late 1800s.The story of the origin of Vietnam's name captures several prominent themes that have run throughout the nation's history.The six-toned dialect of the central Red River delta region, particularly around Hanoi, is regarded as the language's standard form, but significant dialectical variations exist between regions in terms of the number of tones, accents, and vocabulary.Dialectical differences often serve as important symbols of regional identity in social life.