The model view controller pattern is the most used pattern for today’s world web applications. At present there are more than a dozen PHP web frameworks based on MVC pattern.The MVC pattern separates an application in 3 modules:
Model, View and Controller:

Model - The model is responsible to manage the data; it stores and retrieves entities used by an application, usually from a database, and contains the logic implemented by the application.

View - The view (presentation) is responsible to display the data provided by the model in a specific format. It has a similar usage with the template modules present in some popular web applications, like wordpress, joomla, …

Controller - The controller handles the model and view layers to work together. The controller receives a request from the client, invokes the model to perform the requested operations and sends the data to the View. The view formats the data to be presented to the user, in a web application as an html output.