In openSUSE there is a feature called Auto-Login. In short it means that the root can decide which user account should be started as default upon boot, without displaying a login prompt. If you are the only user on a system it might come in handy as you don’t have to type your password each time. Moreover, when installing openSUSE this option is enabled by default.
Though for me it is a possible weakness in my security management. People call me paranoid, I call it common sense and good practice. I’m the only user on my system, but from time to time I have guests in my house (that I both know very good and less good). Auto-Login would mean that they just have to push the power button to have access to almost all my data.
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