Light methodologies are so called not because they are less effective nor applied to simple development efforts. They originally came to be known as "light" methodologies because they were developed, in part, to eliminate much of the documentation that strangles traditional techniques. In other words, they are meant to be less bureaucratic.
Light methodologies are relatively new, having been developed within the last five to six years. Some of these techniques are receiving wide use in the IT industry because they do significantly increase development speeds. However, as with every technique, none are perfect. Each has its own shortcomings.
Although there are several light methodologies in use, we will discuss only a few to provide an understanding about what they are meant to do, compared with traditional techniques, and to round out the discussion about rapid development in general. With this introduction to light methodologies, it is hoped that you can begin to formulate ideas about how to improve your own development schedules and processes. But some words of caution: The best approach is not going to be one of these techniques alone—it is going to be the application of good development practices in conjunction with some of the other rapid development techniques and, perhaps, a variant of these light methodologies.