AngularJS handles the conditional display of elements in the view through the ng-show and ng-hide directives. These directives allow developers to conditionally show or hide elements based on expressions evaluated in the AngularJS scope. This declarative approach simplifies the management of conditional logic in the view, promoting a more maintainable and expressive codebase. Understanding how AngularJS handles conditional display is crucial for creating dynamic and responsive user interfaces.

Handling API rate limits is crucial in scenarios where an AngularJS application makes frequent requests to an API. Implementing mechanisms such as client-side caching, request throttling, and error handling can help manage and respect API rate limits. This ensures that the application operates within the allowed usage thresholds, preventing service disruptions and enhancing overall reliability.

In AngularJS, $watch is used to watch for changes in scope variables and update the view accordingly. It allows developers to track changes in model data and trigger the necessary updates in the UI. Understanding how to use $watch is crucial for building dynamic and responsive AngularJS applications.

To optimize performance, AngularJS controllers should handle events using Observables instead of traditional JavaScript methods. Observables provide a powerful and efficient way to handle asynchronous events, making it easier to manage and react to changes in the application. This is a key concept in AngularJS that enhances the overall responsiveness and performance of the application.

The ng-repeat directive in AngularJS is used to repeat a block of HTML code for each item in a collection. It is particularly useful for rendering lists and tables dynamically based on the data provided. Understanding how ng-repeat works is essential for efficiently displaying data in AngularJS applications and making the UI responsive to changes in the underlying data.

The primary purpose of event handlers in AngularJS controllers is to manage user interactions. Event handlers in controllers respond to user input, such as button clicks or form submissions, and trigger appropriate actions in the application. By handling events, controllers play a crucial role in updating the model and view, ensuring a responsive and interactive user experience in AngularJS applications.

AngularJS handles data binding within expressions through two-way data binding. Two-way data binding enables automatic synchronization of the model and view, allowing changes in one to instantly reflect in the other and vice versa. This feature simplifies the development process by reducing the need for manual updates and enhancing the responsiveness of AngularJS applications. Understanding how two-way data binding works is crucial for efficient data management in AngularJS.

The Routing feature in AngularJS allows for dynamic loading and rendering of views based on application state. AngularJS provides a powerful routing mechanism that enables developers to define routes, associate them with templates and controllers, and navigate between different views. Proper usage of routing enhances the structure and navigation flow of AngularJS applications, making it a fundamental concept for building single-page applications (SPAs).

In advanced AngularJS applications, "controller-as" syntax is used for controller aliasing to enhance readability. It allows you to avoid scope-related issues and makes it clear which controller is associated with a particular section of the view. The "controller-as" syntax is considered a best practice for maintaining clean and readable code in AngularJS.

Modules are a key AngularJS concept that helps in preventing scope conflicts in large applications. Modules provide a way to organize and structure an AngularJS application by encapsulating related components. They help in managing dependencies, defining reusable code, and enhancing modularity. Understanding how to use modules is fundamental for building scalable and maintainable AngularJS applications.