A digital image compiled of many individual squares or bits, each of a specific color to form a graphic, is what we see as a bitmap. Think of the megapixels in your camera or the resolution of your TV. If you looked closely enough, you would see squares upon squares. For most applications, decorators and designers need a solid-color area to determine shape and dimension, which is why they so often need to take those blurry bitmaps and convert them to vector line art.
Converting a digital image to lines or tracing is a necessary process to learn. Various design software contains useful tracing functions. I recommend at least familiarizing yourself with this process, no matter your position or art expertise. It's essential for your understanding and when relaying info to your clients. Check with your software provider for training videos, tutorials, and classes. YouTube is an excellent resource for an abundance of instructional videos.
It's helpful for you to know that there are more variances in type, style, format, color, and extension in bitmaps than any other form of media. Just look at the import and output options in any design software to note a few dozen options, not to mention subsets.
Source: Clay Barbera, Action Illustrated
For insights on bitmap versus vector files and which one is best for digitizing, check out this tip.