For example, B&Q uses a building as market. He installed water, electricity, and network, provided shop, parking lots, and set up a business office to attract shops. The builder provided the infrastructure for these stores,that is IAAS, B&Q provided a service platform for these stores, that is PAAS, shop provided consumers with specific goods, that is SAAS. The platform is between infrastructure and content services. It is often overlooked for ordinary consumers, but it is critical in the industry chain. At home, the computer is IAAS, windows is PAAS, office and other application software is SAAS; mobile phone is IAAS, Android is PAAS, various apps are SAAS. Just a decade ago, the platform also had a name called ISP. Its main characteristics was support and convergence. Its business core was users and payments. IAAS is the user's hardware entry, which is the physical entry. PAAS is the user's software entry, which is the logical entry. They are the two sides of the user's network entry.