How many letters are there in the Chinese writing?

Technically there are zero alphabets in Chinese, but the following two alphabets are used in some situations:

Pinyin (the Latin alphabet for Chinese)
Bopomofo (a native alphabet used as a teaching tool)
There are no letters in Chinese writing, but there are characters.
Chinese characters number in the tens of thousands, though most of them are minor graphic variants encountered only in historical texts. Studies in China have shown that functional literacy in written Chinese requires a knowledge of between three and four thousand characters.
Technically there are zero alphabets in Chinese, but the following two alphabets are used in some situations:

Pinyin (the Latin alphabet for Chinese)
Bopomofo (a native alphabet used as a teaching tool)