Here are some of the common HTTP status codes that you may encounter when working with Salesforce integrations:

1. 200 OK: The request was successful and the server has returned the requested data.

2. 201 Created: The request was successful and a new resource has been created.

3. 204 No Content: The request was successful but there is no response data to return.

4. 302 Found: The requested resource has been temporarily moved to a different location.

5. 400 Bad Request: The request was invalid and could not be processed by the server.

6. 401 Unauthorized: The request requires user authentication, but the user has not provided valid credentials.

7. 403 Forbidden: The user is authenticated, but does not have permission to access the requested resource.

8. 404 Not Found: The requested resource could not be found on the server.

9. 408 Request Timeout: The server timed out waiting for the request.

10. 429 Too Many Requests: The user has exceeded the rate limit for API calls.

11. 500 Internal Server Error: An error occurred on the server while processing the request.

12. 503 Service Unavailable: The server is temporarily unavailable and cannot process the request.

Note that these are just a few examples of common status codes and there are many more that may be encountered depending on the specifics of the integration and the API being used.