Laravel 5.2 call of non-static Query Builder methods like static methods

I am digging deep into Laravel 5.2 architecture. I noticed one thing that there is no static method of some functions, like insert, update in the Illuminate\Database\Eloquent\Model class yet we access it like User::insert()

There is another function performInsert() in the Model class. How does Laravel call performInsert() in the example like this User::insert($data)

I have read in the documentation about facades. But in the documentation it is written that class must extend with Illuminate\Support\Facades\Facade but the Model class doesn't extend with Facade also. Any help?

How is done?

via Chebli Mohamed