Hi @dojoexle. Good thing you're very honest of now knowing them. What I understand about HF19 is :
Hardfork19 - Hardfork is the term defined here for an update in steemit. With this update, your number of upvotes per day will be limited (unlike before). But what's good about this update is that our voting power will be increase 4 times (4x), which means every upvote will be 4 times the revenue than the upvote before.
How should i use hf19