Different run levels

​Linux has different run levels, or the way a system starts or shut down. Different scripts maybe needed to run depending on the run level selected.

For example, if a graphical run level is selected, then a graphical user environment needs to be loaded, it is not needed in a text only mode.

There are seven Linux run levels.

0 - halting of the system.

1 - single user mode. In this mode a minimum number of different scripts run at system startup.

2-5 run levels from 2 to 5 are multiuser run levels.

6 - sixth run level is used to reboot the system.


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