Unsecured loans, credit cards, mortgages, auto loans. The mix of these is taken into consideration. For example, if you were a lender and the borrower owed $200,000 on his house mortgage, you wouldn't shy away from him, but if he owed $50,000 on credit cards, you just might. So if the bulk of your debt is for secured loans, such as auto loans or home mortgages, that's considered more favorable than if the bulk of your debt is unsecured loans, like credit card debt.
You should be very careful in all of your financial activities. All of these things, when taken for granted, affect your credit score. Now you know how vital credit scores and credit history is, so the next time you decide to purchase something and have it charged, think again. Remember, whatever you do will have a direct effect on your score.
------------------------------------------------------------------------------------------------------