The principle of navigation is about ensuring users can move through your site or app easily and intuitively. Clear, consistent navigation helps users quickly find what they’re looking for, whether they're starting on the homepage or landing on a specific page from a search engine. For example, imagine a bookstore app. To create effective navigation, you need to understand users' needs and their way of browsing a book catalog. The main navigation menu might include categories like "Fiction," "Non-Fiction," and "Kids & Teens." Each category should have subcategories based on common genres, for example, "Thrillers" under Fiction and "Business Books" under “Non-Fiction.”