I have already written article to integrate Salesforce with other Salesforce instance around 3 years back. In last 3 years, Salesforce has changed a lot. This time I will integrate Salesforce with other Salesforce only only in 5 lines of code, can you believe it 🙂 ? Check my old article, and its around 50+ lines of code with security control.
What is Named Credential ?
A named credential specifies the URL of a callout endpoint and its required authentication parameters in one definition. You can simplify the setup of authenticated Apex callouts by specifying a named credential as the callout endpoint. You can instead specify a URL as the callout endpoint and register that URL in your organization’s remote site settings. In that case, however, you handle the authentication in your code. Doing so can be less secure and especially complicated for OAuth authentication.
Long description short , “using Named Credential, we can make call out to external system without supplying username or Password”.