Zend certified PHP/Magento developer

What event is fired after a customer places an order?

so I’ve been looking to do some adjustments with an observer by listening to the event that is fired after a user successfully places an order. But, I don’t know which event I’m looking for. My best guesses are:

  1. checkout_submit_all_after
  2. checkout_controller_onepage_saveOrder
    I got the above events from This list of Magento 2 events

Can someone help me understand which event I need? and which of the ones I provided, if any,is correct and why? and what’s the difference between both?