Mandarin Chinese has the most native speakers worldwide according to widely cited language estimates.
Mandarin is a group of Sinitic varieties spoken chiefly in mainland China and Taiwan, with substantial communities elsewhere. Standard Chinese, based largely on the Beijing dialect, is the official language of the People's Republic of China and Taiwan and one of Singapore's official languages. It is also one of the six official languages of the United Nations.
Estimates commonly place the number of native Mandarin speakers at roughly 900 million or more, though totals vary depending on whether related varieties are grouped together. Mandarin is therefore the leading language by first-language speakers, while English generally leads when native and second-language speakers are combined.
Written Chinese uses characters rather than an alphabet. Standard Mandarin uses four main lexical tones plus a neutral tone, so pitch can change a word's meaning. The Romanization system pinyin is widely used for pronunciation, language learning, dictionaries, and digital input, but it does not replace Chinese characters in ordinary formal writing.