APN is short for Access Point Name,APN Name, to identify the names of types of services, GPRS is divided into two categories: CMWAP Access WAP service (through GPRS), CMNET (except the WAP service are outside the CMNET with, for example, to connect to the Internet, etc.).
The English full Name is Access Point Name,  is through the Internet phone must be in a configuration parameters, which determines your mobile phone through which Access to Access the network.