In the fast-paced world of web development, having the right tools can dramatically streamline your workflow and enhance your productivity. Here are the Top 5 Essential Tools Every Web Developer Should Use:

1. Visual Studio Code - A powerful, lightweight code editor that supports numerous programming languages and offers a wide range of extensions to customize your development environment.
2. Git - Essential for version control, Git allows developers to track changes, collaborate with others, and manage different versions of their projects seamlessly.
3. Chrome DevTools - A set of web developer tools built directly into the Google Chrome browser, making it easier to inspect elements, debug JavaScript, and optimize performance.
4. Figma - A collaborative interface design tool that's perfect for creating prototypes and wireframes, enabling web developers to work closely with designers.
5. Postman - An indispensable API testing tool that simplifies the process of sending requests and viewing responses, crucial for backend development.

Writing clean and maintainable code is essential for any software development project to ensure that it can be easily understood, modified, and extended over time. Here are some best practices to achieve this goal:

1. Use descriptive naming conventions: Choose variable, function, and class names that clearly convey their purpose and intent. This will help others (and your future self) quickly grasp the functionality of the code.
2. Comment judiciously: While code should be self-explanatory, adding meaningful comments can provide context for complex logic. However, avoid redundant comments; they can clutter the code.
3. Follow consistent formatting: Stick to a coding style guide that outlines rules for indentation, line length, and spacing. This increases readability and helps in collaboration.

In addition to following these tips, consider implementing version control systems like Git to track changes and collaborate with other developers effectively. Regular refactoring of your code is also crucial; it allows you to optimize and simplify code without changing its functionality. Lastly, don’t underestimate the importance of unit testing; it ensures that individual components of your code work as expected, which ultimately contributes to its maintainability and reliability.

In the fast-paced world of web development, it's easy to stumble into common mistakes that can hinder both the functionality and user experience of a website. First, one prevalent issue is neglecting the importance of responsive design. With users accessing websites from a variety of devices, it's crucial to ensure that your site adapts seamlessly to different screen sizes. Failure to implement responsive design can lead to a frustrating experience, driving potential users away. To fix this, utilize CSS frameworks like Bootstrap or employ flexible grid layouts that automatically adjust to various resolutions.

Another frequent pitfall is overlooking the significance of search engine optimization (SEO) during the development process. Developers may focus heavily on technical aspects but forget to include SEO best practices such as optimizing title tags, meta descriptions, and page load speed. To remedy this, conduct regular SEO audits using tools like Google PageSpeed Insights, and ensure that your content management system supports easy SEO adjustments. By prioritizing both design and optimization, you can create a website that attracts and retains visitors effectively.