We have an external application which we would like to authenticate using salesforce.com. I have read salesforce.com documentation for using OAuth but i am not clear how to implement this feature (We do not want Client to manually go and create Client key). Basically we want someone to access our system but login authentication will be verified by salesforce. Imagine a website which authenticates by using Salesforce.com credentials. Any help is appreciated.

We have an external application which we would like to authenticate using salesforce.com. I have read salesforce.com documentation for using OAuth but i am not clear how to implement this feature (We do not want Client to manually go and create Client key). Basically we want someone to access our system but login authentication will be verified by salesforce. Imagine a website which authenticates by using Salesforce.com credentials. Any help is appreciated.