1. A virtual operating area supporting customized definition, comprising: one or more virtual operating areas which include one or more area element objects and operating authority rules, the area element objects including users, file data, tools and/or other virtual operating areas, the users including virtual operating area creators and operators, the file data including computer documents in various formats, the tools being software and hardware systems, the operating authority rules specifying operating authority of the users for the area element objects; a share relationship table to specify share relationship regarding operating authorities of different users for a same virtual operating area or a same area element object; a virtual operating area engine which is a supporting software to support the users to operate the virtual operating areas and the area element objects; a tool configuration document integrated in the virtual operating area engine to describe tool calling fashion, running locations of the tools, input parameters and output result storage location of the tools; a repository including a virtual operating area repository to store the virtual operating areas and related information thereof which include virtual operating area identifiers, the area element objects, the operating authority rules and the share relationship tables; a tool repository to store the tools, a tool registration table and a tool receiving table, a user repository to store the users and user identifiers, the users including computer system operators or automatic equipments; a tool processor loading the tool registration tables, the virtual operating area repository, the virtual operating area engine and the virtual operating areas to generate the tool configuration document corresponding to the virtual operating areas to register tool identifiers, the virtual operating area identifiers of the tool running locations, a pair table of the tool input parameters and the area element objects, a pair table of the tool output parameters and the area element objects, operating authority information of the operators, tool execution code storage addresses and tool execution code calling fashions, and an user I/O interface to interact with the users.