Example:
If u are trying to use the method create in php artisan tinker :
App<class_name>:create
You will notice the error :
IlluminateDatabaseEloquentMassAssignmentException with message...
The reason is going to your class and add: protected $fillable
class <class_name> extends Model
{
protected $fillable = ['<column_name>' , '<column_name>', '<column_name'];
}