Yu-Gi-Oh! player and collectors should know the different rarities for the cards. Here is a quick list:
Common (C): Common cards have no special quirks to them. No holofoil, no fancy lettering, just your standard card. They also come in three flavors (note that there is no visual way to determine if a Common is under any of the below rarities):
Rare (R): Rare cards are similar to Common cards except they use silver or black holofoil for the card name letters. These are the most common rarity of card to find next to Common cards.
Super Rare (SR): Super Rare cards have the card art printed in in holofoil.
Holofoil Rare (HFR): Holofoil Rare cards have the card art printed holofoil and include a holofoil coating.
Ultra Rare (UR): Ultra Rare cards are a combination of Super and normal Rare cards, with holofoil lettering and holofoil. The difference here is that the name is printed in gold foil instead of silver or black.
Ultra Rare (Pharaoh's Rare) (URP): For all intents and purposes, cards with this rarity are Ultra Rares, but have the Millennium Rare's hieroglyphs applied over the foiling.
Ultimate Rare (UtR): Similar to the Ultra Rares, except that both the art, borders, and card 'buttons' (depicting the card type and, with monsters, their level) are embossed in a relief effect. These cards are generally reprints of Super and Ultra (and in the English game, normal Rare) cards of the recent sets, within those recent sets (meaning that you can sometimes get an Ultra Rare card and its Ultimate Rare counterpart in the same set). Be careful with these cards, as their unique printing also makes them thinner and flimsier than normal cards.
Secret Rare (ScR): Secret Rares (also known as Promo Rares) are the same as the Ultra Rare cards, except that the foil on the name is holographic silver, while the holofoil art is polarized, giving a cross-hatched look to it.
Ultra Secret Rare (UScR): Ultra Secret Rare cards have silver holofoil letters and holofoil backgrounds.
Secret Ultra Rare (ScUR): Secret Ultra Rare cards have gold holofoil letters and use the polarized holofoil of Secret Rare cards.
Prismatic Secret Rare (PScR): These have Silver holographic letters and a prism holofoil background.
Parallel Rare (PR): Parallel Rare cards have the same polarizing effect of a Secret Rare over the ENTIRE card. They come in a few flavors noted below. These cards are the trickiest to find, as they're only printed as certain promos, and their appearance can also be mistaken as being fake.
Starfoil Rare (SFR): Starfoil Rare cards are similar to Parallel Rare cards and were introduced to TCG with Battle Pack: Epic Dawn. These cards have a sort of outer-space pattern. The 5th card in every pack of Battle Pack: Epic Dawn is a Starfoil Card and every card in the set is available in this type.
Starlight Rare (SLR): Starlight Rare cards have the same horizontal holographic foil pattern as a Prismatic Secret Rare, but applied to the whole card rather than only the artwork, similar to the Platinum Secret Rare. The only areas of the card to which the foil is not applied are the card text box, empty Link Arrows, and portions of the artwork.
Ghost Rare (GR): Ghost Rare is a new rarity introduced in the TCG version of Tactical Evolution. It appears to have a very shiny silver lettering, much like a Secret Rare, with some colors removed from the card image, and the entire card appears to be holographic. The overall effect of these changes is a pale, "Ghost-like" appearance to the card art, especially when scanned. When this was written, there were only four Ghost Rare TCG Cards: Rainbow Dragon, Elemental Hero Chaos Neos, Rainbow Neos and Honest.
Gold Ultra Rare (GUR): Gold Ultra Rare is a new type of rarity introduced in the Gold Series. It has gold lettering and a holographic foil image like an Ultra Rare, but also has a holographic gold image border, lore text border, and card border. On Monster Cards, the Level Stars are embossed in gold foil, similar to what is found on Ultimate Rares.
Original Source: eBay Guides but updated many times over by YuGiOhCardGuide.com.