Hanyu Pinyin, or simply pinyin, is the most common romanization system for Standard Chinese. In official documents, it is referred to as the Chinese Phonetic Alphabet. It is the official system used in China, Singapore, Taiwan, and by the United Nations. Its use has become common when transliterating Standard Chinese mostly regardless of region, though it is less ubiquitous in Taiwan. It is used to teach Standard Chinese, normally written with Chinese characters, to students already familiar with the Latin alphabet. The system makes use of diacritics to indicate the four tones found in Standard Chinese, though these are often omitted in various contexts, such as when spelling Chinese names in non-Chinese texts, or when writing non-Chinese words in Chinese-language texts. Pinyin is also used by various input methods on computers and to categorize entries in some Chinese dictionaries. Hànyǔ literally means 'Han language'—meaning, the Chinese language—while pinyin literally means 'spelled sounds'.

Standard Chinese is a modern standard form of Mandarin Chinese that was first codified during the republican era (1912‒1949). It is designated as the official language of mainland China and a major language in the United Nations, Singapore, and Taiwan. It is largely based on the Beijing dialect. Standard Chinese is a pluricentric language with local standards in mainland China, Taiwan and Singapore that mainly differ in their lexicon. Hong Kong written Chinese, used for formal written communication in Hong Kong and Macau, is a form of Standard Chinese that is read aloud with the Cantonese reading of characters.