According to FICO, all information in their scores come straight off of an individual's credit report. Since information on file may vary from one credit bureau to another, it is very common for an individual to have three different (although usually not wildly divergent) credit scores. Collected information is weighted by FICO software in approximately the following ratios:

Payment History: 35%
Have payments been made in a timely manner? Is there a consistent history of slow payments? Have there been charge-offs, collection activity, occurrences of foreclosure, bankruptcy, suits, liens, or repossessions?

Amounts Owed: 30%
What is the total debt, debt on individual accounts, number of accounts, percent of available credit converted to debt? If credit lines or cards are exhausted, this will have a negative impact on a credit score.

Length of Credit History: 15%
How long has the borrower been a creditor? An insufficient credit history or lack of credit history will have a negative impact on a credit score. FICO, in fact, will not calculate a credit score unless a credit report shows an account which has been open for six months or more and at least one account that has been updated in the previous six months.

New Credit: 10%
The number of recently opened credit accounts and their proportion to total open accounts and/or the number of recent credit inquiries may be viewed as an indication of cash flow problems. However, new credit, if indicating re-establishment of a positive credit history following credit problems will have a positive impact. (Certain inquiries such as those put through by companies seeking customers for "pre-approved" credit card offers or those by existing creditors monitoring existing customers credit performance are not considered in the credit score.)

Types of Credit Used: 10%
Too many credit card accounts, revolving retail charge accounts, or loans from certain types of lenders such as finance companies can have a negative effect on scores.

These are guidelines for the general population. Evaluation criteria for persons, for example with newly established credit, may be different.

Lenders may also integrate information from your loan application, such as your job, length of employment, or whether you own a home.

Certain types of information are not used in compiling a credit score. U.S. law prohibits race, color, religion, national origin, sex and marital status from being used in any type of credit evaluation including scoring. Age is not a factor in constructing a FICO score but may be used in other kinds of credit scoring. Other information such as location of residency, interest rates on current loan obligations, and child or family support obligations may be used in some credit scoring programs but are not factors in a FICO score.

FICO scores range from around 300 to about 850. Approximately 1 percent of the population with established credit has credit scores below 500 and another 13 percent score from 500 to 600. By far the largest group, 28 percent, is in the 750 to 799 scoring range. About 11 percent of the population is in that rarified area above 800 points. The median credit score (the point where 50 percent rank higher and 50 percent rank lower) is 723. Americans obviously care about and take care of their credit.

As stated earlier, a bad FICO is not necessarily the end of the road, but it will affect your loan. Interest rates and other loan features can be impacted directly by credit scores.