Original Link: http://alistapart.com/article/your-website-has-two-faces
When a user interface—intended for human consumption—reflects too much of a system’s internals in its design and language, it’s likely to confuse the people who use it. But at the same time, if data doesn’t conform to a specific structure, it’s likely to confuse the machines that need to use it—so we can’t ignore system requirements, either.
People and machines parse information in fundamentally different ways. We need to find a way to balance the needs of both.