Because the Chinese language is a logographic language in which one "character" corresponds roughly to one "word" or meaning there are vastly more characters, or glyphs, than there are on a standard computer keyboard.
To allow the input of Chinese using standard keyboards a variety of keyboard input methods have been designed.
Keyboard input methods can be classified in 3 main types: by encoding, by pronunciation, and by structure of the characters. The following are just some samples of Chinese input methods. Many of those input methods have variations. Full Pinyin and Double Pinyin are variation of the Pinyin input method. In addition, the methods which require the user to select a character from a menu generally have sophisticated methods for guessing which characters the user intends based on context.
Different people are most comfortably with different methods and each standard has its strengths and weaknesses. For example, for someone who is already familiar with pinyin, the pinyin method can be learned most quickly. However, the maximum typing rate is limited, and learning the system is difficult for some who doesn't know pinyin. Wubi takes much effort to learn, but expert typists can enter text much faster than the phonetic methods. Because of these factors, there is no likelihood of a "standard" method evolving.
Other means of inputting Chinese characters are not widely used but include stylus and tablet, with hand-writing recognition software, as the most common alternative, and then OCR optical character recognition (OCR) and voice recognition. As with English language all these methods suffer from high error rates.
Pronunciation
Character Structure
Combination of Pronunciation and Character Structure
Character Encodings
Main article: Chinese character encoding
Other