The Chinese writing has more than 50,000 characters, but if you know 5,000 of the most common characters you can read a newspaper or modern novel. There are 5 types of Chinese characters which are pictographs, simple ideographs, compound ideographs, character borrowing, and phonetic compounds.
There are four stages of writing. These stages are Jia-gu wen or Oracle Bone, Da zhuan or Greater Seal, Xiao zhuan or Lesser Seal, and Li shu or Clerkly Script. The earliest stage is Jia-gu wen or Oracle. Li shu or Clerky Script is basically known as the modern Chinese script.