Init System

In Unix-based Operating systems, including Linux, an Init system is required to enable optimal use of a OS.

Init systems, also referred to as "Initialization Systems," are a key component in the booting phase of an OS as their main task is to initialize other required processes and services to grant a functional and optimal OS. After booting up, Init systems begin to work in the background as a daemon process, their main tasks shifts from initializing components to becoming a direct or indirect ancestor of any other processes that may spawn in under the current working environment; adding on, these systems typically adopt all orphaned processes and can terminate any and all zombie processes. Seeing that their role in a operating system is to maintain functionality throughout the system, in a Unix-based Operating system, a kernel is required to have a functional and usable Init system, a kernel panic will occur if—for whatever reason—a kernel is unable to find, start, or maintain the OS's Init.

There are 2 different groups of Inits, depending on the functionality of an Init determines if it should be consider a Traditional Init System (TIS) or a Modern Init System (MIS). Although the end goal of both types remains consistent between the two, TIS and MIS approach each task differently and support different use cases for different hardware.