If you go to eBay and search the sports card category using the term "1/1" you will get almost 3,000 different items.  I bet that only half of them are true 1/1 cards.  The hobby has spawned some very creative people trying to get you to think a card is serial numbered 1/1 when its really not.  People's reasons for a card to be a 1/1 are just plain outrageous and too many people are falling for their scam.  Below are some of the biggest excuses for a card to be a 1/1:

• Jersey Number - Say a card is numbered 10/100.  The seller could say that the card is a 1/1 because the player's jersey number is 10 and thats the only one like it.

• First One Made - People may say that a card is a 1/1 because it was the first one made.  For example, a card numbered 1/100.

• Last One Made - People may say that a card is a 1/1 because it was the last one one made.  For example, a card numbered 100/100.

• Statistic - Someone may claim a card is a 1/1 because the number matches a statistic from their career.  For example, height, weight, birthday, debut, etc...

• Math - By doing addition, subtraction, multiplication, and division people may claim a card is a 1/1 because just by doing math and using the numbers the answer may match up with the players birthday, jersey number, or statistic from their career.  For example, a card numbered 12/20 being considered a 1/1 because 12 + 20 = 32, and 32 is the player's jersey number.

• Only One They Have Seen - Some people may say a card is a 1/1 because it is the only one that they have seen.

• High Grade - Cards have been considered 1/1 because the seller thinks that it would get a high grade.

These are just a few of the many tricks sellers try to pull with potential buyers.  The only way a card can be a true 1/1 is if it is serial numbered by the manufacturer.  Check the seller's feedback and do your research on that specific brand of cards to see whether there are real 1/1's within the product.

Andrew Chrisman runs Sports Card Info, http://sportscardinfo.wordpress.com/

A blog that provides hobby news, stories, thoughts, and fake card information.