There are many uses for Chinese Romanization. Most broadly, it is used to provide a useful way for foreigners who are not skilled at recognizing Chinese script a means to read and recognize Chinese names. Apart from this general role, it serves as a useful tool for foreign learners of Chinese by indicating the pronunciation of unfamiliar characters. It can also be helpful for clarifying pronunciation—Chinese pronunciation is an issue for some speakers of other mutually unintelligible Chinese varieties who do not speak Mandarin fluently. Standard keyboards such as QWERTY are designed for the Latin alphabet, often making the input of Chinese characters into computers difficult. Chinese dictionaries have complex and competing sorting rules for characters, and romanization systems can simplify the problem by listing the characters by their Latin form alphabetically.
Romanization systems for other Chinese varieties are indicated in the information box on the right side of this page.
The Indian Sanskrit grammarians who went to China two thousand years ago to work on the translation of Buddhist scriptures into Chinese and the transcription of Buddhist terms into Chinese, discovered the "initial sound", "final sound", and "suprasegmental tone" structure of spoken Chinese syllables. This understanding is reflected in the precise Fanqie system, and it is the core principle of all modern systems. While the Fanqie system was ideal for indicating the conventional pronunciation of single, isolated characters in written Classical Chinese literature, it was unworkable for the pronunciation of essentially polysyllabic, colloquial spoken Chinese varieties, such as Mandarin.
Aside from syllable structure, it is also necessary to indicate tones in Chinese romanization. Tones distinguish the definition of all morphemes in Chinese, and the definition of a word is often ambiguous in the absence of tones. Certain systems such as Wade-Giles indicate tone with a number following the syllable: ma1, ma2, ma3, ma4. Others, like Pinyin, indicate the tone with diacritics: mā, má, mǎ, mà. Still, the system of Gwoyeu Romatzyh (National Romanization) bypasses the issue of introducing non-letter symbols by changing the letters within the syllable, as in mha, ma, maa, mah, each of which contains the same vowel, but a different tone.
The Wade, Wade-Giles, and Postal systems still appear in the European literature, but generally only within a passage cited from an earlier work. Most European language texts use the Chinese Hanyu Pinyin system (usually without tone marks) since 1979 as it was adopted by the People's Republic of China.