'Use Credential File' in oracle data integrator in data server what is it used for?

I want to explore Oracle data integrator , i am not able to understand what does 'Use credential File' option in Data server does in Oracle data integrator. If anyone can explain it would be helpful and i want to improve performance of my oracle data integrator script as well, any ideas on that as well.

Ok, now I think that I understood. You run ODI in Cloud. You will need a credential File in order to connect to your database. The way you obtain that credential file, is: Credential files are downloaded from the ADW console to the ODI host in the Oracle Cloud Infrastructure (OCI).

Note: When ODI is deployed from the Marketplace, client credential folders are downloaded from autonomous databases that exist in the OCI compartment containing ODI.

If ADW is in a different compartment than ODI follow the steps below.

Download the Credentials

Connect to the ODI host using VNC. Refer to the Deployment blog above for details.

Launch Firefox from the Applications>Favorites list.

Follow the steps in Downloading Autonomous Data Warehouse Credentials to obtain the client credentials compressed folder containing the wallet and network configuration files used by ODI to make the connections.

The entire way of connecting is described here.