Moving towards the documentation of a project or application, afterclassifying the classes and their interfaces, and before starting to implement themethods of a class, the interface should be documented. This includes writing a classcomment and method comments for every class in the project. These should be defined in adequate detail to identify the overall purpose of each class and method.

Along with analysis and design, documentation is a further area that is often neglected by beginners. It is not easy for inexperienced programmers to see whydocumentation is so important. The reason is that inexperienced programmers usuallywork on projects that have only a handful of classes, and that are written in the spanof a few weeks or months. A programmer can get away with bad documentation whenworking on these mini-projects.

However, even experienced programmers often wonder how it is possible to write thedocumentation before the implementation. This is because they fail to appreciate that good documentation focuses on high-level issues, such as what a class or method does, rather than low-level issues, such as exactly how it does it. This is usuallysymptomatic of viewing the implementation as being more important than the design.