The visa laws, in China, change regularly. Please note that these visas are accurate as of December of 2011. Most of these visas are obtainable without legal assistance. However, in cases where you will be having foreign staff working in Korea (Z Visa), it is advisable to consult counsel in order to be in compliance with Chinese tax and corporate law.
D Visa: Permanent Residency Visa
The D Visa is, in most cases, only available for those that are married to Chinese or those having lived in China for over five years and has made significant investments in China.
L VISA: Tourist Visa
A tourist visa needs to be obtained, normally, prior to entering China. These visas, normally, allow one to stay in the country for no longer than three months. You are able, in most cases, to obtain a multiple-entry visa that is good for one year.
F VISA: Business Visa
The F Visa, normally, allows for the presence in China for a period of six months and is good for, normally, a period of one year.
X Visa: Student Visa
Student Visa are obtainable by contacting the school that you intend to study with. The visas are, normally, available for as long as the period of study.
Z Visa: Work Visa/Joining Family
Upon obtaining the visa abroad, the holder should enter China report residence and receive a residence permit within 30 days of entering China.