Hi,
I will go to China(Guangzhou) for trip on October. In between, I will go to Hong Kong ,Macau and Shenzhen from Guangzhou and finally will back to Malaysia from Guangzhou too. Do I need to apply another visa (in order to travelling to Hong Kong,Macau and Shenzhen from Guangzhou)? What is the difference between single entry visa and multi-entry visa? Is it I only have to apply the China visa then can travel to few places in China (eg:HK,Macau,Shenzhen)?

Thank you.