Understanding PHP syntax is crucial for writing clean and efficient code. PHP, being a server-side scripting language, has its own set of rules and conventions that developers must follow. To maintain readability and organization in your code, it's essential to adhere to best practices such as proper indentation and the use of meaningful variable names. For instance, starting variable names with a dollar sign ($) and utilizing camelCase or underscores can improve clarity. Remember, well-structured PHP code not only makes it easier for you to maintain but also simplifies collaboration with other developers.

To further enhance your understanding of PHP syntax, consider these key tips for writing clean code:

1. Consistent Formatting: Stick to a uniform style throughout your codebase.
2. Commenting: Use comments generously to explain complex code sections, making it easier for others (and yourself) to understand.
3. Modular Code: Break larger scripts into functions or classes to encapsulate functionality.

When developing with PHP, developers often encounter common pitfalls that can hinder the performance and security of their applications. One major mistake is neglecting to handle user input properly. Failing to sanitize and validate input can lead to vulnerabilities such as SQL injection or cross-site scripting (XSS). To avoid this, always use prepared statements with database queries and employ built-in functions like filter_var() for validating data.

An additional pitfall is the improper use of session management, which can result in session fixation attacks or session hijacking. To mitigate these risks, ensure that you regenerate session IDs regularly using session_regenerate_id() and configure secure session settings in your php.ini file. Moreover, it’s crucial to implement proper error handling and logging to maintain application stability and enhance security. Following these best practices helps ensure a robust PHP application that is both efficient and safe.

PHP continues to be a top choice for web development due to its simplicity and flexibility. One of the primary advantages of PHP is its ease of learning, making it accessible for beginners to start their coding journey. Additionally, it offers a vast ecosystem of frameworks like Laravel and Symfony, which streamline development processes and enhance code quality. With an active community backing PHP, developers can easily find resources, support, and plugins to address their needs, ensuring that they are never alone on their coding quest.

Furthermore, PHP is highly compatible with various database systems, particularly MySQL, which is a significant factor for building dynamic websites. Its ability to handle large volumes of traffic and offer support for numerous content management systems (CMS) like WordPress makes it a reliable choice for developers. The language's continual updates and improvements also contribute to its longevity in the web development landscape, ensuring that it remains relevant and efficient in solving modern web challenges.