Proxy Signup

Using the SignupRequest object, you can programmatically create a new organization without any system-generated emails being sent to the user. You can then obtain an OAuth access token to log in to the organization and make API requests from it, without any action by the user. This is called proxy signup because it enables you to create and operate the organization on the user’s behalf, without their knowledge that you’re using Salesforce behind the scenes. – IFG