What should I learn? DNA? APIC-EM? ACI? NSO? So many SDN solutions! Help! (Part 1)

In this video, Hank Preston from Cisco DevNet helps us decide which Cisco SDN platforms we should learn. Should we be learning DNA Center? APIC-EM? ACI? NSO? What do those even mean? And what should I as a network engineer be learning?

DevNet Start Now Page:
http://bit.ly/2DE0RU6

Networking Dev Center:
http://bit.ly/2zFV50m

Busting NSO Myths
https://www.youtube.com/watch?v=YwUj3-9swzE

Free NSO Download
http://bit.ly/2y0C4nb

DNA Center Platform on DevNet
http://bit.ly/2xRONcB

ACI on DevNet
http://bit.ly/2y4PtKO