There are two main types of applications: the actual demands and requests harmless. When making a mortgage loan, car loan or other type of credit, the creditor has the right to request your credit profile. This is a real demand which may have impact on your credit score. Actual applications may also be made by collection agencies.

When a company with whom you already have a relationship makes a subsequent credit check in order to offer additional credit products, this is a harmless application that does not affect your credit score. The innocuous requests may also be generated in other circumstances, such as when a company where you already have an account consults your credit profile to your account management. When you ask your own profile, this is as a harmless application.

Returning to the real demands. These play a role with respect to your credit score because it is you who initiate the request. If your profile includes a long list of credit card applications, creditors may think that you are starving credit. This could give you a higher level of risk and your credit score could fall.
The situation is slightly different when it comes to secured loans. If you are looking for a mortgage or car, several potential creditors might ask your profile, even if you are actually looking for one loan. Thus, many requests related to a mortgage or car loan, over a short period, could count only as a single application, as the creditor, and thus have minimal impact on your credit score.
Do you know who should check your credit profile the most? You. By ordering a few times your credit report each year, you will ensure that it is very precise at all times. And remember that when you ask your profile, it is a harmless application that does not affect your score.