Hi,
What is a class?
A class can be defined a structure that is composed of two things:
- Data Members.
- Methods.
A class is designed to be reused, when using a class we dont have to know, how it is designed, we just need to know the interface and methods signatures.

Why using a class in vb?
We use class to create composant that can be reused in other application.
Such example, creating a class that do the following:
- Create an ODBC connection to a Database,
- Create an OLEDB connection,
- Get a recordset from the DB,
- Execute Function (Insert, Update, ...statements)
- Check if a connection status to a DB,...
As you can se this functions are already used to deal with a DB.

How to use a class?
You have to create an instance of that class (called object)
We have a compoent called dataLayer in which there is a class called clsDataLayer, some of it's methods are ODBCConnect,GetDisRecordsetPage...

Dim oData as new datalayer.clsdtalayer
Dim MyCnn as new adodb.Connection

set MyCnn =oData.ODBCConnect("DsnEssai")

Regards