As with most, if not all, programming languages, there are many frameworks available for PHP and each seem to have their own unique pros and cons. Also, as technology moves forward, server-side frameworks in particular sometimes become entirely outdated due to new security practices, new programming paradigms and other reasons.
Laravel is an MVC PHP Framework that has certainly been creating a lot of attention and generating popularity. It was created in 2011 by Taylor Otwell as he wanted to provide a more advanced, flexible alternative to Codeigniter (another PHP Framework)(Source), specifically to have built in user authentication and authorization capabilities. With Laravel 2 (in late 2011), the template language Blade was added for Laravel views to give a simpler, cleaner syntax that is both minimal and easy to understand. Fastforwarding, Laravel 5.4 was released in January of 2017, with 5.5 potentially coming by the end of 2017. Components such as Artisan (Laravel's command line), Eloquent (Object Relational Mapping for Databases), Elixir (an API for managing tasks for pre-processors), and built in validation rules and now coming with Vue.js out of the box makes Laravel a very powerful choice. This is strengthened when considering its flexibility such as allowing developers to create and assign their own Service, Worker, Job and other types of classes.
Many trends are showing that most PHP Frameworks are fading out, at least at this point, other than Laravel. Sitepoint published "The State of PHP MVC Frameworks in 2017" stating that trends for previously popular frameworks such as Zen, CakePHP, CodeIgniter have all but phased out. The article still includes Symfony in the running as Symfony 3 was still yet to be released (Symfony was released in August, 2017).
Originally concived by SensioLabs, the PHP framework Symfony was first published in 2005 (sympfony.com) under an Open-Source MIT License. It was inspired by Java's Spring Framework and took aim to be extremely customizable, building robust applications from small too enterprise levels, ability to reuse code to reduce repetative tasks, and have a low performance overhead (wikipedia.org/wiki/Symfony). It also included existing PHP tools such as Doctrine for database storage/object relational mapper (also cold ORM) and so on. Details can get very technical so to shorten, it quickly became very popular in still is used very often despite Laravel bundling many Symfony components with its framework.