I've been reading The Pragmatic Programmer, which I bought some time ago, and today on the bus ride to work I read the concept of tracer bullets.

It's really nothing new, but I liked the analogy. When you fire a gun in the dark, sometime you need to use tracer bullets, which are special bullets that leave a phosphorus trail from the gun to where it hits. They are often used to avoid tedious calculations necessary if firing regular bullets in the dark. The feedback (where it hits) is immediate.

In the realm of programming, you'd use this concept for a step further in prototyping, you "prototype" the entire system, and the interactions between its parts, instead of each one individually. You build the skeleton of the application, which you can later fill with code.

This also gives you immediate feedback to see if each part will work and communicate correctly with each other, and it's specially useful for building stuff you have never built before.

I'm starting to like this book