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Weeks of programming can save you hours of planning!
DevDocs combines multiple API documentations in a fast, organized, and searchable interface.
You don't have to reinvent the Web site to publish some documentation for your project. Take advantage of GitHub Pages to build almost point-and-click doc sites.
API documentation is the number one reference for anyone implementing your API, and it can profoundly influence the developer experience. Because it describes what services an application programming interface offers and how to use those services, your documentation will inevitably create an impression about your product—for better or for worse.
It doesn’t matter how good your software is, because if the documentation is not good enough, people will not use it.
Documenting your code is important. It tells other developers what the code does, why it is constructed in a certain way, and how to use it. Good documentation saves them time when they are trying to perform a certain task that isn’t straightforward. It will probably also save you time because the human brain can only store so much information. Even your own code will confuse you at some point in the future.