System startup, inittab, and run levels

When we power on the Linux system, shell scripts are run one after another
and the Linux system is initialized. These scripts start various services, daemons, databases, and applications, as well as mount discs. Even during the shutting down of the system, certain shell scripts are executed so that important system data and information can be saved to the disk and the applications are properly shut down. These are called boot, startup, and shutdown scripts. These scripts are copied during installation of the Linux operating system in your computer. As a developer or administrator, understanding these scripts may help you in understanding and debugging the Linux system. If required, you can customize these scripts if the need arises.

The kernel...