What Is a Rarity Symbol?
Each Pokémon card features a small icon near the set number, usually found in the bottom-left or bottom-right corner of the card. This icon is known as the rarity symbol, and it’s the simplest way to identify how rare a card is within its set.
I never really memorized the rarity symbols myself, so I’m including an image created by reddit user DON-616 that illustrates them so clearly—even I was finally able to tell them apart.

In addition to rarity symbols, Pokémon cards come in various styles that affect their visual appeal and value. Holo cards feature shiny foil on the artwork, while Reverse Holo cards have foil on everything except the artwork. Full Art cards extend the illustration across the entire card, often with textured foil. Illustration Rares and Special Illustration Rares showcase unique, artistic designs and are highly collectible. Ultra, Secret, and Hyper Rares are premium cards with special finishes like gold or rainbow foil. Lastly, Promo cards are exclusive to products or events and marked as such.
