Explain the difference between Laravel 4 and Laravel 5?

There are vast differences between laravel 4 and laravel 5 regarding LTS, features, file structures, etc.

Laravel 4 was the one who brought significant popularity to the Laravel framework, but it’s not updated anymore, and also it lacks a lot of functions released in Laravel 5.

• Laravel 4 released May 2013 but Laravel 5 released in February 2015.
• Laravel 5 has LTS Supports. It means the LTS version stands for Long Term Support. It implies that bugfixes for that version will be provided for two years, until the next LTS version.
• In Laravel 5, Controllers, middleware, and requests are now grouped under the app/Http directory.
• A new app/Providers directory replaces the app/start files from previous versions of Laravel 4.x
• Application language files and views have been moved to the resources directory.
• New route: cache Artisan command to drastically speed up the registration of your ways.
• Laravel 5 now supports HTTP middleware, and the included authentication and CSRF "filters" have been converted to middleware but not in Laravel 4
• User registration, authentication, and password reset controllers are now included out of the box, as well as simple corresponding views, which are located at resources/views/auth
• A database queue driver is currently involved in Laravel, providing a simple, local queue driver that requires no extra package installation beyond your database software.
• Laravel Socialite is an optional, Laravel 5.0+ compatible package that provides painless authentication with OAuth providers.
• Laravel now includes the powerful Flysystem filesystem abstraction library, providing pain-free integration with local, Amazon S3, and Rackspace cloud storage - all with one, unified and elegant API.
• The favorite dd helper function, which dumps variable debug information, has been upgraded to use the fantastic Symfony VarDumper

In contrast to Laravel 4 to 5 version differences, which were breaking and huge, 5.x and 5.y versions are not that different. Some functions added, some updated/removed, but the core structure remains the same.