There are two major forms of this, OpenID and OAuth. OpenID is only used for identification, while OAuth gives some form of limited access that is sometimes restricted enough that it’s basically just used for identification. The permissions granted by using OAuth varies by site, but they usually show you what information they will be sharing before you accept.
There are benefits for both the developers running the site and for the end-user.
For example, BambooHR, the cloud-based HR software we use where I work, allows me to log in with gmail. Google is an OpenID authentication provider so no information is shared. Also, since I’m always logged into my gmail, it’s just a single click to “log in with gmail” and I don’t have to type any passwords or anything. (In fact, I never had to set up a password to begin with)
For more info on how OAuth and OpenID are different, there’s a nice graphic here.
There are two major forms of this, OpenID and OAuth. OpenID is only used for identification, while OAuth gives some form of limited access that is sometimes restricted enough that it’s basically just used for identification. The permissions granted by using OAuth varies by site, but they usually show you what information they will be sharing before you accept.
There are benefits for both the developers running the site and for the end-user.
For example, BambooHR, the cloud-based HR software we use where I work, allows me to log in with gmail. Google is an OpenID authentication provider so no information is shared. Also, since I’m always logged into my gmail, it’s just a single click to “log in with gmail” and I don’t have to type any passwords or anything. (In fact, I never had to set up a password to begin with)
For more info on how OAuth and OpenID are different, there’s a nice graphic here.