As its name implies, the kernel is at the core of each UNIX system and is loaded in whenever the system is started up -referred to as a boot of the system.
It manages the entire resources of the system, presenting them to you and every other user as a coherent system. You do not need to know anything about the kernel in order to use a UNIX system. This information is provided for your information only.
Amongst the functions performed by the kernel are:
- managing the machine's memory and allocating it
to each process.
- scheduling the work done by the CPU so that
the work of each user is carried out as
efficiently as is possible.
- organising the transfer of data from one part
of the machine to another.
- accepting instructions from the shell and
carrying them out.
- enforcing the access permissions that are in
force on the file system.