Actually, I do not really know what is the best way to learn about commond words. I learned by staying here, reading many articles. Maybe try to find an article that is specifically about explaining HIVE (or STEEM). Or go to https://hiveblocks.com/@dagadu and read some info about your account... if you do not understand something, try to look it up. If you cannot look it up, ask someone.

EDIT: Peakd actually has a good FAQ (https://peakd.com/about/faq). It will probably be better to read it first.