Figure 10.1 shows an overview of the Microsoft ADO model. Unlike the DAO model, the ADO object model is not hierarchical.
The Connection object defines a session for a user for a data source. Although the ADO object model is not considered to be hierarchical, the Connection object is considered the highest-level ADO object. After you have established a Connection object, you can use it with multiple recordsets. This improves performance and greatly simplifies your programming code.
A Connection object must be declared before it is used. The declaration looks like this: