is it Linux os GNU/Linux

[Ahmed Bilal Jan]

Many folks around feel that Linux should really be called GNU/Linux.
This is because Linux is only the kernel(the program in the system
that allocates the machine's resources to the other programs that you
run), not the applications that run on it. Most of the basic command
line utilities were written by the Free Software Foundation(an
organization with aim to develop and fund the development of free
software) while developing their GNU operating system. Among those
utilities are some of the most basic commands like cp, mv, lsof, and
dd.
GNU site quotes
“Many computer users run a modified version of the GNU system every
day, without realizing it. Through a peculiar turn of events, the
version of GNU which is widely used today is often called “Linux”, and
many of its users are not aware that it is basically the GNU system,
developed by the GNU Project.
There really is a Linux, and these people are using it, but it is just
a part of the system they use. Linux is the kernel: (the program in
the system that allocates the machine's resources to the other
programs that you run). The kernel is an essential part of an
operating system, but useless by itself; it can only function in the
context of a complete operating system. Linux is normally used in
combination with the GNU operating system: the whole system is
basically GNU with Linux added, or GNU/Linux. All the so-called
“Linux” distributions are really distributions of GNU/Linux.”
In a nutshell, what happened was, the FSF started developing GNU by
writing things like compliers, C libraries, and basic command line
utilities before the kernel. Linus Torvalds (best know for having
initiated the development of linux kernel), started Linux by writing
the Linux kernel first and using applications written for GNU