“The /proc directory is a strange beast. It doesn’t really
exist, yet you can explore it. Its zero-length files are neither
binary nor text, yet you can examine and display them. This special
directory holds all the details about your Linux system, including
its kernel, processes, and configuration parameters. By studying
the /proc directory, you can learn how Linux commands work, and you
can even do some administrative tasks.“Under Linux, everything is managed as a file; even devices are
accessed as files (in the /dev directory). Although you might think
that ‘normal’ files are either text or binary (or possibly device
or pipe files), the /proc directory contains a stranger type:
virtual files…”