PHP is a popular scripting language designed for web development to produce dynamic web pages. Coursera's PHP skill catalogue teaches you how to effectively utilize this server-side language in developing both simple and complex web applications. You'll learn about the fundamentals of PHP, including its syntax and structure, as well as advanced topics like object-oriented PHP, data manipulation, and form validation. Additionally, you'll gain insights into PHP's integration with SQL databases and how to handle exceptions and errors. Acquiring this skill will allow you to create dynamic, interactive websites, and it is an essential component for any aspiring web developer or software engineer.