People may not know you are my aunt. This comment in addition to the other is not to spam you but because you haven't done an introduceyourself blog yet (no hurry) this post is the only one you have.
Someone just made a post that might help explain the different currencies:
https://steemit.com/steem/@tony.jennings/explaining-steem-steem-power-and-steem-dollars-to-someone-unfamiliar-with-crypto-currencies
If you want to deep dive into how this site actually works. Here is the white paper:
https://steem.io/SteemWhitePaper.pdf
One of the founders of steem is Dan Larimer and he is @dantheman on this site:
You would likely enjoy his latest post:
https://steemit.com/philosophy/@dantheman/why-do-we-fight-to-change-the-world
Thanks, will check it out!