What is the difference between Collection & Repository & Factory classes?

Question

I am trying to understand when to is use which according to the best practice. for exg.

To get some data like (product,customer) what should be used Collection ? To set some data into product etc what should be used ?

Need some clarity in here.

Thankyou

Answer 1

Magento strictly follows and recommends design patterns

Collection Repository This implementation use to manipulate entity objects but not able to create new one.

$repo = $this->myRepository();
$object = $repo->getById($myId);
$object->setData('something', 'somethingDifferent');
$repo->save($object);

Collection Factory This implementation use to manipulate entity objects and able to create new one.

$object = $this->myFactory->create();
$object->setData('something', 'somethingDifferent')->save();