If you've ever seen a curl post somewhere with people starting off like "i'm an hp, pl, 3a" and were like "what in the actual &*&% are these people talking about?", you're not alone. All she's really saying is that her curls are high porosity, love protein, and her curl shape (big ringlets with the waves).
Porosity is basically how flat the cuticle layer of the hair lays down and it's ability to absorb moisture and protein - the stands can be coarse or fine, you can have lots of hair (density) or even a thinner less dense amount.
A simple and reasonably effective way to figure out your porosity is The Float Test. Fill a glass with water and add a few strands of your hair. If it floats, it doesn't take on the water and is low porosity, if it sits half way it's average porosity, and if it sinks to the bottom, it's high porosity.
Knowing your hair's porosity is important because it can help you determine the best way to offer it moisture and protein, and the best way to seal said moisture and protein in with a styling product. Below is a link about porosity from naturallycurl.com - they have lots of great information so rather than regurgitate all of it, I'll link to it here When you've determined your porosity, you're ready for Bootcamp #3