It is a good idea to order copies of your credit report from all three of the largest companies at least once a year, because mistakes can happen and the information each company has on file may be different from what the others have. A growing crime called identity theft is another reason to check your credit. By checking your report once a year, you are more likely to find out if you are the victim of crooks who use your personal information, such as Social Security number and date of birth, to apply for credit in your name and use it to buy jewelry, electronics or even cars