I just put together a few screencast from ONOS.
IMO, they are a great way to get you introduced to ONOS. Then, if you think it sounds good, go ahead and look further.
- This screencast is an overview of ONOS.
- This other screencast shows how can get ONOS running with Docker.
- Here you can get started setting the dev environment for ONOS.
- Here you can check the code for a simple ONOS app
More information can be found in the wiki:
I hope this is helpful!