A clear understanding of event driven programming is as important as an understanding of any other decision structure. Especially in this age of connected computers and computers that are 'always there' just waiting to spring into action (like the computers in your car or at the supermarket), this style of computing is everywhere.
But it wasn't always like this! In the early days of programming, most 'data processing' was done in 'batches'. A 'batch' of data that needed processing (like a day's receipts at a store, or a month's payroll records) would be collected and then processed all at one time. They did it this way for two reasons. First, computers were a LOT more expensive then and second, the technology to do it any other way just hadn't been invented yet. So if you ever run into "old timers" (like ... well ... me) who get misty-eyed about working through the night to solve problems so the 'customer master update' could run, this is what we're talking about.
The book states that, "Every object in Visual Basic has a predefined set of events it can respond to." That was a lot more true of VB 6 than it is in VB.NET. In VB.NET, you can actually change how code responds to events. Understanding how it's done tells you a lot about how VB.NET actually works.
The book shows you how to find events that an object will respond to using the drop down lists in Visual Studio .NET. But the code resulting from clicking an item on the list is where the programming is.
