Credit reporting agency, such as Equifax, Trans-Union, collect regularly information about your financial behaviour for:
Creditors use your credit score and your credit file as a reference to determine if you can obtain a money loan and to calculate the interest rate.
Owners and employers can also use your credit file as a reference to evaluate your reliability.
It is very important to know all the informations about your credit file. If you have a bad backup in credit, it can be complicated to obtain a loan or a credit card.
Your score will change according to the evolution of your credit file.