When you apply for any new line of credit - for example, a new credit card - the creditor requests a copy of credit report from one or more of the credit bureaus. The creditor will evaluate your credit report, a credit score, or other information you provide (such as income or debt information) to determine your credit worthiness, as well as your interest rate. If you're approved, that new card - called a tradeline, will be included in your credit report and updated about every 30 days.
A credit report includes information on where you live, how you pay your bills, and whether you’ve been sued or have filed for bankruptcy. Nationwide credit reporting companies sell the information in your report to creditors, insurers, employers, and other businesses that use it to evaluate your applications for credit, insurance, employment, or renting a home.