PHP is a server-side scripting language that is embedded in HTML and a widely used language in web development. Also, we say that

PHP is a server scripting language, and a powerful tool for making dynamic and interactive Web pages

 It is used to manage dynamic content, databases, session tracking, even build entire e-commerce sites. It is integrated with a number of popular databases, including MySQL, PostgreSQL, Oracle, Sybase, Informix, and Microsoft SQL Server.

These are important PHP applications that are developed in PHP language or using its framework:

• Content Management System (WordPress, Joomla, Drupal, Magento)  
• Making user-friendly dynamic websites 
• Web-based applications and development of sites.
• E-commerce websites and applications.
• Data Analytics and Representation.

Advantages of PHP :

1. The most important advantage of PHP is that it is an open-source platform and free of cost to developing projects. No need for any license for the software.
2. They are often downloaded anywhere and readily available to use in web applications.
3. It is platform-independent, PHP-based applications can run on any OS like UNIX, Linux, and windows, etc.
4. The application can easily be loaded which is based on PHP and connected to the database. it’s mainly used due to its faster rate of loading over slow internet and speed than another programing language.

Disadvantages of PHP :

1. It is an open-source platform so not that secure due to ASCII text files will be easily available.
2. It is not suitable for giant content-based web applications.
3. PHP frameworks got to learn to use PHP built-in functionalities to avoid writing additional code.
4. PHP doesn’t allow change or modification in the core behavior of online applications.
5. It is widely believed by the developers that PHP features a poor quality of handling errors. PHP lacks debugging tools, which are needed to look for errors and warnings.
6. PHP has fewer debugging tools in comparison to other programming languages.