One fine example that can illustrate this is as follows. This means that IP forwarding by this machine isn't allowed by the kernel. Thus we have enabled IP forwarding on our Linux machine. The actual listing was really lengthy. What's given below is a much shorter version.
Lets learn a little more about the contents of the directories with the numerical naming scheme.
Let's look at the contents of one of these directories. Before executing this command you need to log in as root because the various processes running on the system may be owned by various other users. As usual you have access only to the processes that you have started. After having logged in as root just execute the above command for any of the directories and compare the output to what is listed above. Yes, the contents of all the directories are the same irrespective of the directory you choose to view as these directories contain the various parameters and the status of the process whose PID is the name of the current directory that you are in.