Front-end and back-end developers are two distinct roles in web development, each responsible for different aspects of building web applications. Here’s an overview of what front-end and back-end developers do:

Front-End Developer:

1. User Interface (UI) Development: Front-end developers focus on creating the user interface of a web application. This includes designing the layout, visual elements, and overall look and feel of the application.
2. User Experience (UX) Design: They ensure that the web application is user-friendly and provides an optimal user experience. This involves considering factors like navigation, responsiveness, and accessibility.
3. HTML, CSS, and JavaScript: Front-end developers use HTML (Hypertext Markup Language) for structuring content, CSS (Cascading Style Sheets) for styling, and JavaScript for adding interactivity and functionality to web pages.
4. Responsive Design: They make web applications responsive, meaning they adapt to different screen sizes and devices, such as desktops, tablets, and smartphones.
5. Cross-Browser Compatibility: Front-end developers ensure that the web application works correctly and looks consistent across various web browsers, including Chrome, Firefox, Safari, and Edge.
6. Front-End Frameworks: They often use front-end frameworks like React, Angular, or Vue.js to streamline development and create interactive components.
7. Testing and Debugging: Front-end developers test their work across different browsers, devices, and screen sizes to identify and fix issues. They also use debugging tools to address errors.

Back-End Developer:

1. Server-Side Logic: Back-end developers are responsible for the server-side logic of a web application. They handle data processing, authentication, and server operations.
2. Database Management: They design, develop, and maintain databases to store and retrieve data efficiently. Common database management systems include MySQL, PostgreSQL, MongoDB, and SQL Server.
3. Server-Side Programming: Back-end developers use server-side programming languages like Python, Ruby, Java, PHP, or Node.js to build the functionality of the web application.
4. API Development: They create APIs (Application Programming Interfaces) to enable communication between the front-end and back-end components of the web application. APIs allow data exchange and integration with third-party services.
5. Security: Back-end developers implement security measures to protect the web application and user data. This includes measures against common vulnerabilities like SQL injection and cross-site scripting (XSS).
6. Scalability: They plan for scalability, ensuring that the web application can handle increased traffic and data as the user base grows. This involves optimizing server performance and architecture.
7. Server Deployment: Back-end developers deploy the web application to web servers or cloud platforms (e.g., AWS, Azure, Heroku) and configure the hosting environment.
8. Testing and Quality Assurance: They perform testing and quality assurance on server-side components to ensure data integrity, performance, and reliability.
9. Version Control: Back-end developers use version control systems like Git to track code changes and collaborate with team members.

Both front-end and back-end developers work together to create a fully functional web application. They collaborate closely to ensure that the user interface (front end) seamlessly interacts with the server-side logic (back end) to deliver a complete and engaging user experience. Depending on the project, some developers may specialize in one of these roles, while others may work as full-stack developers, capable of handling both front-end and back-end tasks.