"Framework" is one of those terms you may come across when you are very young, if you are particularly fond of computers and you start to be fascinated by the concept of "programming", or when you grow up, out of curiosity or practical needs, maybe related to your profession. But what are they and what are they for?
Frameworks are large predefined blocks of code into which programmers go to insert the actual content of an application. They are actually "frames", predefined structures that are used as the basis for software development.
You can use a Framework by calling its methods, its properties and providing "Callbacks" (code block passed as a parameter to another function), Listeners (interface that contains the methods related to the type of event you want to intercept) and other implementations of the Observer Pattern.
But are the Frameworks necessary?
The answer is no, but it is a tool that can help you develop better and faster.
Better because it gives you the confidence to produce an application that is totally in line with the rules of the industry, that is structured and that is both optimizable and upgradeable.
Faster because it allows developers to save time by reusing generic modules to focus on other areas without being limited by the Framework itself.
Focus on value-added work
The basic principle of the Framework and the reason why it is used is only one: not starting from scratch but "sitting on the shoulders of giants". Imperative: eliminate problems, low value-added tasks (you will no longer have to work on developing generic components) and focus on your business.
A concrete example? A Framework will allow a developer to save even 2 or 3 days of work creating an Authentication Form by allowing them to develop specific components and conduct tests to ensure that everything is fully functional and robust.
Maintenance and upgradeability of a Framework
In the long run, a Framework ensures the longevity of your applications and makes maintenance operations more agile and safe. All it takes is a development team to update and manage the applications on which Framework has been installed with ease.
On the other hand, it must be stressed that a Framework is not a room with no exit. In the case of Symfony, a web application development framework written in PHP language and following the MVC (Model-View-Controller) paradigm, it would be wrong to think you can't get out of the "framework": it is still PHP language and is natively interoperable with any PHP library.
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