WordPress was originally created as a blogging platform and evolved into a content management system. Hence, most of the core functionalities are implemented on the concept of posts and pages. In web applications, we need to go way beyond these basic posts and pages to build quality applications. Custom menu pages play a vital role in implementing custom functionalities within the WordPress admin dashboard. Let's consider the various types of custom pages in the default context:
Options pages: These are used to manage the options of the application. Even though the option pages are generally used for theme options, we can manage any type of application-specific settings with these pages.
Custom menu pages: Generally, these pages are blank by default. We need to implement the interface as well as the implementation for catering to custom requirements that can't take advantage of WordPress' core features.