How does the HTTP protocol work?

HTTP (Hypertext Transfer Protocol) is a request-response protocol. The client (e.g., a web browser) sends an HTTP request to the server. The server then processes the request and sends back an HTTP response, which contains the requested resource (e.g., an HTML page, an image) or an error message.

What are RESTful APIs? Provide an example use case.

REST (Representational State Transfer) is an architectural style for designing networked applications. A RESTful API is an API that adheres to the constraints of REST.

Example Use Case:

A client can make a GET request to `/api/users/123` to retrieve the data for the user with ID 123. The server would then respond with the user's data in a format like JSON.

Explain the difference between cookies, sessions, and tokens.

Cookies: Small pieces of data stored on the client's browser. They are sent with every request to the server and are mainly used for tracking.

Sessions: Data stored on the server that is associated with a specific user. A session ID is stored in a cookie on the client's browser to identify the user.

Tokens: A piece of data that is created by a server and contains information to identify a user. They are often used for authentication in APIs.

What role does JavaScript play in modern web applications?

JavaScript is a scripting language that enables you to create dynamically updating content, control multimedia, animate images, and pretty much everything else. It is the primary language for creating interactive web pages.

In modern web development, JavaScript is used in:

• Frontend Frameworks: React, Angular, Vue.js
• Server-Side Development: Node.js
• Mobile Apps: React Native, NativeScript

Compare monolithic vs microservices architectures.

Monolithic Architecture: The entire application is built as a single, unified unit. All components are interconnected and interdependent.

Microservices Architecture: The application is broken down into a collection of smaller, independent services. Each service is self-contained and can be developed, deployed, and scaled independently.

What is responsive web design, and how can it be achieved?

Responsive Web Design is an approach to web design that makes web pages render well on a variety of devices and window or screen sizes.

It can be achieved using:

• Flexible Grids: Using relative units like percentages instead of fixed units like pixels.
• Fluid Images: Ensuring that images can scale within their containing elements.
• Media Queries: Applying different CSS styles based on the characteristics of the device, such as its width, height, or orientation.