PHP is a general-purpose scripting language that is widely used in web development. While most popular for web programming, you can also use PHP to create standalone applications and backend build scripts and utilities. PHP is actually an abbreviation of PHP: Hypertext Processor. A web server like Apache or Nginx executes PHP code through a module or CGI interface. When the server receives a request directed to a PHP script, the PHP code is interpreted and executed. It will then return a response that may be HTML, JSON, or binary image data. Many PHP frameworks like Laravel and Symphony make the process of building web applications with PHP simpler and quicker. PHP is also free and open-source, which means anyone can download a PHP executable for their operating system and start coding.

HTML is the markup language that defines the structure of web pages. Every web page uses HTML. It is not a programming language, but a subset of XML. Web browsers parse HTML to determine how a web page and its elements, like headings, paragraphs, and images, will look when rendered. Static HTML pages can be served directly by a web server and usually have a .htm or .html extension. PHP is a scripting language that runs on a web server. It must be executed to return results. Usually identifiable with the .php extension, PHP is commonly used in web development to generate HTML on dynamic websites. The difference is that PHP can return more than HTML; it also generates other text-based data like JSON, as well as images and binary data. PHP developers work on server-side or back-end code, while HTML is used to develop the front-end of a website.

Since the PHP programming language is prevalent in web development, most PHP careers involve building and maintaining web applications and websites. There are many types of web development careers to choose from if you know PHP. Marketing agencies, advertising agencies, and many other businesses use content management systems like WordPress and Drupal for their websites. These companies need PHP developers to add custom functionality to these popular platforms when the built-in features are not enough. Another career choice for a PHP developer is in e-commerce, customizing PHP e-commerce platforms like Magento or Zen Cart. Other web development companies using PHP frameworks like Laravel or Zend Framework need PHP developers to build custom websites and applications. In some PHP jobs, developers have to write custom PHP code from scratch.