In the imperative programming development model, you write code that calls methods on OPC Data Client objects. You prepare and pass in the arguments necessary, and get back the results that you can process further.

This is the traditional model, “natural” to software developers. Its advantage is that you have high level of control over what is happening, and you can structure the code the way you like it. The disadvantage is that you may end up writing more code than it is necessary, compared to other models.