Without graphics images, Microsoft Windows-based applications would be pretty dull. Some applications depend on images for their usefulness, but any application can be spruced up with the addition of decorative clip art from a variety of sources. Windows bitmaps are arrays of bits mapped to display pixels. That might sound simple, but you have to learn a lot about bitmaps before you can use them to create professional applications for Windows.
This chapter starts with the "old" way of programming bitmaps—creating the device-dependent GDI bitmaps that work with a memory device context. You need to know these techniques because many programmers are still using them and you'll also need to use them on occasion.
Next you'll graduate to the modern way of programming bitmaps—creating device-independent bitmaps (DIBs). If you use DIBs, you'll have an easier time with colors and with the printer. In some cases you'll get better performance. The Win32 function CreateDIBSection gives you the benefits of DIBs combined with all the features of GDI bitmaps.
Finally, you'll learn how to use the MFC CBitmapButton class to put bitmaps on pushbuttons. (Using CBitmapButton to put bitmaps on pushbuttons has nothing to do with DIBs, but it's a useful technique that would be difficult to master without an example.)