What is a Pokemon standard set foil?
Standard set foil cards are cards that have a holofoil design in the picture of the Pokemon on the Standard card. These are almost always rares (besides specially printed cards) and will be marked with a *H for their rarity [Example](https://bulbapedia.bulbagarden.net/wiki/Kingdra_(Burning_Shadows_31)).
What is a parallel set in Pokemon TCG?
The "parallel" set simply refers to what is more commonly called "reverse-holo" cards. Each card has a reverse-holo version of itself, with the exception of a few full-art cards. Here's an example! Pretty neat if I do say so myself! Hope that cleared things up for you!
What set are my Pokemon cards from?
To identify the set, look for a little symbol at the bottom of the card, next to the card number. There are a bunch of these set symbols… 5-6 sets are released every year, each with a different set symbol, and they've been printing cards since 1999!