How do you tell what rarity on a yu-gi-oh card?

Answer 1

Rarity these days is more about the card's style rather than how hard it is to obtain. A card in secret rare style might be just a mass produced reprint, for example. Only an experienced player would be able to say for sure, you just have to learn the set names and know what that means.

Rarities,

Common - a basic, plain card.

Rare - Silver text only, gold text from GENF onwards.

Super Rare - shiny picture, non-shiny title text.

Ultra Rare - shiny picture, gold title text.

Secret Rare - sparkly, striped foil effect on the picture, silvery text but with a rainbow tint.

Ultimate Rare - these cards are textured, on the level stars, attribute, part of the picture, etc. Recent ones have a textured border too.

Ghost Rare - the picture is a silver 3D holograph.

Parallel Rare - These have a shiny sheen to them, with either a square pattern (Hobby League) or dots (Duel Terminal).

There are then some other ones, like a special secret rare that appeared on certain video game promos.