class Class is generally used when you want to load a particular class specifically,
Very commom example of using this class "Class" is while connecting to anydatabase by using jdbc.
Class.forName () //with different parameters,
this methods return the object of class or interface associated with the given String argument.
i am using this class as
Class.forName ("jdbc:odbc:.....");
Connection con = DriverManager.getConnection ()//other parameters
Class.forName(), loads the DriverManager , with the reference of the dRiver passed as argument.
There are other usage also , but i think this will give you a general idea about this class "Class".