Credit bureaus receive consumer credit information from banks and other businesses. When another business with a "permissible purpose" requests to see a credit report, the credit bureau sells it to them.
Law Regarding Credit Bureaus
The Fair Credit Reporting Act (FCRA) is a federal law that defines how credit bureaus are supposed to operate. The FCRA gives consumers the right to an accurate credit report. If you find errors in your credit report, you're allowed to dispute these errors with the credit bureaus. The credit bureau is then required to do an investigation and correct the errors when necessary.
Credit Bureaus Providing Free Credit Reports
You also have the right to order your credit report from the three credit bureaus. Another law, the Fair and Accurate Credit Transactions Act, gives you the right to one free credit report each year from each of the three major credit bureaus. You can order this annual credit report through AnnualCreditReport.com.