Cisco ACI - ELI5

So I know this isn't the "ELI5" sub but I feel that it would be relevant and provide value for others as well.

I have a CCNA R/S and am starting to learn more about ACI in general for a customer. I have taken a Intro to ACI class o. Udemy but want to hear from folks who have worked in production with it and have had to explain or describe it.

While I may understand the basic logical concept of ACI, I feel that I do not want to limit the responses to things I may already know (which is limited considering I am only at the CCNA level in R/S)

Thank you in advance for all of your insight. You all rock!