But, some organisations need to access Salesforce directly from another application (and not implemented SSO), we can add username and password include as login parameters to direct login to Salesforce, here we go:
https://www.salesforce.com/login.jsp?un=user@email.com&pw=secret
The same applied for sandbox:
https://test.salesforce.com/login.jsp?un=user@email.com&pw=secret
You also can redirect user to a specific record, such as: account, contact or report:
https://test.salesforce.com/login.jsp?un=user@email.com&pw=secret&startURL=/00190000005lXMZ
NOTE: Since your password is in the URL, everyone could see it, so be cautious.
NOTE: Since your password is in the URL, everyone could see it, so be cautious.