Angular components are the fundamental building blocks of Angular applications. They encapsulate the logic, data, and presentation of a portion of the user interface, allowing for a modular structure that enhances maintainability and reusability. Each component consists of three core elements: the template, which defines the view; the class, which contains the business logic; and the metadata, which provides Angular with information about the component. By organizing code into these discrete components, developers can easily manage and scale their applications.

To create a robust application, one should follow best practices in structuring these components. Here are some key strategies to consider:

1. Reusability: Design components that can be reused across different parts of the application.
2. Separation of Concerns: Ensure that each component has a single responsibility and is not overly complex.
3. Input and Output Properties: Use @Input() and @Output() decorators to facilitate data binding and communication between components.

When it comes to developing robust applications using Angular, adhering to best practices is crucial for ensuring not only efficiency but also maintainability and scalability. Here are some top Angular best practices that every developer should follow:

1. Modular Architecture: Break down your application into feature modules to promote reusability and separation of concerns.
2. Consistent Naming Conventions: Adopt a consistent naming strategy for components, services, and modules to improve code readability.
3. Use Observable Patterns: Leverage RxJS for managing async data streams, which results in better performance and cleaner code.
4. Optimize Performance: Utilize the Angular CLI's built-in tools, such as Ahead-of-Time (AOT) compilation, to enhance loading speeds.
5. Utilize Lazy Loading: Implement lazy loading for feature modules to decrease the initial load time of your application.

In addition to the foundational practices mentioned above, incorporating testing strategies into your workflow remains essential. Here are some vital testing practices:

1. Create Unit Tests: Write unit tests for components and services to ensure each piece of functionality works as intended.
2. End-to-End Testing: Use frameworks like Protractor for comprehensive testing of the user interface and user interactions.
3. Effective Error Handling: Implement global error handling to manage exceptions gracefully and enhance user experience.
4. Stay Updated: Regularly update your Angular version to the latest stable release to benefit from new features and performance improvements.
5. Maintain Documentation: Keep your code well-documented to aid team collaboration and future maintenance.

Mastering Angular routing is essential for building scalable and maintainable web applications. In this step-by-step guide, we will cover the fundamentals of Angular routing, from the basics of setting up routes to more advanced techniques like lazy loading and route guards. First, ensure you have Angular CLI installed and create a new Angular project. You can add routing to your application during the setup by using the --routing flag. This will generate a basic routing module that you can customize according to your needs.

Once you have your routing module in place, start by defining your routes in the RouterModule.forRoot([]) method. Each route should map a path to a specific component. For instance, { path: 'home', component: HomeComponent } creates a route for the home page. To improve navigation and user experience, consider implementing lazy loading for feature modules. This way, modules are loaded on demand, enhancing your application's performance. Additionally, adding route guards can help protect certain routes and manage user permissions effectively.