Lenders use your score to determine your eligibility for loans, lines of credit, credit cards, etc. If your score is in the upper range (i.e. 720+), you're more likely to receive favorable interest rates and terms; if your score is lower, you'll likely be charged higher interest rates or you may get turned down altogether.
The good news? No credit score lasts forever. Your score can go up or down depending on how you manage your credit.
One final note: Your credit score may go up and down throughout the month, depending on your credit card balance and other factors. Don't be discouraged; this is normal fluctuation. As long as over the long-term it's consistently moving forward, you're doing well. Use ScoreMaster® to help you better understand these score fluctuations.