Structured reference

Trading card field guide

Read the three units in order or jump straight to a definition. Each lesson starts with the answer, then adds examples, data, and related tools.

lessons
8
units
3
rarity tiers
5

Unit 01

How cards are made and opened

Start with the creation process, then learn the language of booster packs and pack openings.

  1. 1.1Definition

    AI Card Generator

    An AI card generator is a tool that uses machine learning models to create custom trading cards from user inputs - typically a photo. The AI analyzes the image, generates original card artwork in a specific style (like Pokemon or anime), and assigns stats, abilities, and a card name automatically.

    $184Bglobal AI market size in 2024, powering tools like AI card generators
  2. 1.2Definition

    Booster Pack

    A booster pack is a sealed, randomized package of trading cards - typically containing 10-15 cards - sold as the primary method for expanding a collection. Each pack follows a fixed rarity distribution: mostly commons and uncommons, with a guaranteed rare slot and a small chance of pulling ultra-rare or secret rare cards.

    $4.49MSRP per standard Pokemon TCG booster pack as of 2025
  3. 1.3Definition

    Pack Opening

    A pack opening is the experience of unsealing a randomized booster pack to reveal the trading cards inside. Each pack contains a mix of common, uncommon, and (if you're lucky) rare cards - and the moment of flipping to the rare slot is what makes pack opening one of the most addictive rituals in the hobby.

    60M+Pokemon TCG Pocket downloads within 45 days of its October 2024 launch

Unit 02

Rarity and finish

Separate pull frequency from surface treatment, including foil and holographic effects.

  1. 2.1Definition

    Trading Card Rarity

    Trading card rarity is a classification system that controls how often a specific card appears in sealed product like booster packs. Rarer cards have lower pull rates, better artwork, and stronger gameplay abilities - making them more valuable to collectors and players alike.

    $2.6Mpaid for The One Ring MTG card, the most expensive trading card ever sold
  2. 2.2Definition

    Foil Card

    A foil card is a trading card with a thin metallic layer - usually aluminum - applied to its surface, creating a reflective, mirror-like sheen. Unlike holographic cards that display rainbow diffraction patterns, foil cards produce a uniform metallic reflection. The terms are often used interchangeably by casual collectors, but they're technically different processes.

    2-5xtypical price premium for foil card variants over their non-foil equivalents in Magic: The Gathering
  3. 2.3Definition

    Holographic Card

    A holographic card is a trading card with a reflective, rainbow-shifting surface created by microscopic diffraction gratings embossed into metallic foil. When light hits the surface at different angles, the gratings split it into spectral colors - producing the signature shimmer that collectors chase.

    $420,000sale price for a PSA 10 1st Edition Base Set Charizard holo in 2022

Unit 03

Condition and grading

Learn how centering, corners, edges, and surface affect a physical card's grade.

  1. 3.1Definition

    Card Centering

    Card centering refers to how evenly the printed image is positioned within a trading card's borders. Perfectly centered cards have equal border widths on all four sides. Off-center cards - where the image shifts left, right, up, or down - receive lower grades from professional grading services and are worth less on the secondary market.

    60/40maximum front centering ratio allowed by PSA for a Gem Mint 10 grade
  2. 3.2Definition

    Card Grading

    Card grading is a professional service where a third-party company evaluates a trading card's physical condition and assigns it a numerical grade from 1 (Poor) to 10 (Gem Mint). The card is then sealed in a tamper-proof case - called a slab - with its grade permanently displayed.

    80M+cards certified by PSA since its founding in 1991