Say OAuth instead of SSO (#2148)

Signed-off-by: Jonah Aragon <jonah@triplebit.net>

docs/basics/account-creation.md

@@ -45,15 +45,11 @@ Should a service get hacked, you might start receiving phishing or spam emails t
 
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-### Single sign-on
+### "Sign in with..." (OAuth)
 
-!!! note
-  
-    We are discussing Single sign-on for personal use, not enterprise users.
+OAuth is an authentication protocol that allows you to register for a service without sharing much information with the service provider, if any, by using an existing account you have with another service instead. Whenever you see something along the lines of "Sign in with *provider name*" on a registration form, it's typically using OAuth.
 
-Single sign-on (SSO) is an authentication method that allows you to register for a service without sharing much information, if any. Whenever you see something along the lines of "Sign-in with *provider name*" on a registration form it's SSO.
-
-When you choose single sign-on in a website, it will prompt your SSO provider login page and after that your account will be connected. Your password won't be shared but some basic information will (you can review it during the login request). This process is needed every time you want to log in to the same account.
+When you sign in with OAuth, it will open a login page with the provider you choose, and your existing account and new account will be connected. Your password won't be shared, but some basic information typically will (you can review it during the login request). This process is needed every time you want to log in to the same account.
 
 The main advantages are:
 
@@ -62,12 +58,12 @@ The main advantages are:
 
 But there are disadvantages:
 
-- **Privacy**: a SSO provider will know the services you use.
-- **Centralization**: if your SSO account gets compromised or you aren't able to login to it, all other accounts connected to it are affected.
+- **Privacy**: the OAuth provider you log in with will know the services you use.
+- **Centralization**: if the account you use for OAuth is compromised or you aren't able to login to it, all other accounts connected to it are affected.
 
-SSO can be especially useful in those situations where you could benefit from deeper integration between services. For example, one of those services may offer SSO for the others. Our recommendation is to limit SSO to only where you need it and protect the main account with [MFA](multi-factor-authentication.md).
+OAuth authentication can be especially useful in those situations where you could benefit from deeper integration between services. Our recommendation is to limit using OAuth to only where you need it, and always protect the main account with [MFA](multi-factor-authentication.md).
 
-All services that use SSO will be as secure as your SSO account. For example, if you want to secure an account with a hardware key but that service doesn't support hardware keys, you can secure your SSO account with a hardware key and now you essentially have hardware MFA on all your accounts. It is worth noting though that weak authentication on your SSO account means that any account tied to that login will also be weak.
+All the services that use OAuth will be as secure as your underlying provider's account. For example, if you want to secure an account with a hardware key, but that service doesn't support hardware keys, you can secure the account you use with OAuth with a hardware key instead, and now you essentially have hardware MFA on all your accounts. It is worth noting though that weak authentication on your OAuth provider account means that any account tied to that login will also be weak.
 
 ### Phone number