commands for operating systems

Unix and linux are very different from any version of DOS, and have only a very few commands in common with DOS (cd is the only one that comes to mind immediately).

Examples:
DOS Unix
copy cp
dir ls
del rm
type cat
cd cd
rd rmdir
md mkdir

There are many books on unix and linux which list the commands. I suggest finding a book on linux that is one version behind the current one. Your local bookstore will likely have this on a clearance table for under $20. The differences in commands between the versions are effectively zero -- new versions only add commands and features.

Good luck.

Here are the 6 to 7 DOS commands and their Unix / Linux

DOS (Lin)UX
--- -------
CD cd
MD mkdir
RD rmdir
DIR ls
DEL rm
COPY cp
REN mv
CLS clear
EDIT vi
HELP man
CHKDSK fsck
??? shutdown (to shutdown unix/linux)

Is this what you are looking for?

I would recommend going to:
www.redhat.com
www.linux.org
They have admin and installation manules on site. As with most flavors of Unix/Linux commands stay similar throught, with only slight differences.

Here are links to your answer:

http://www.learninglinux.com/Linuxcommands.htm

http://www.linuxdoc.org/HOWTO/DOS-Win-to-Linux-HOWTO.html

Unix and Linux commands are very different from DOS commands. The only feature that they really have in common is that they work from the command line. From that point on, how the individual commands function is very different. Generally speaking, Unix and LInux commands are a lot more versatile and powerful than DOS commands, allowing a user to manoeuver through the file system in a very straightforward manner. The important thing to learn right from the start is that the file structures that are used by Unix and Linux are not similar to those used by DOS (and by extension, MSWindows). That makes learning the Unix and Linux commands akin to learning a second language. It isn't that difficult, but it takes a fair bit of work. Something else you will undoubtedly learn about Unix and Linux commands very quickly: the names are terse in structure, but they are also very logical in that each letter or two generally represents an entire word. (eg: 'fsck' stands for 'file system check', 'chmod' for 'change mode', etc), and filenames are not limited to the 8+3 format of DOS filenames.
If you are going with Linux (or Unix) I recommend that you find and participate in your local Linux Users Group (LUG). Since essentially all the information you will ever need about Linux is free (including program source code) you will also find a vast amount of up-to-the-minute information and programs via the Internet. Look for the HOW-TO's, and sites that register and provide software drivers, as well as operating system upgrades.
As for the basic commands, I have yet to find a definitive book that walks through how to use each command. As a start I recommend "Linux In A Nutshell", and the appropriate 'Unleashed' book specific to your operating system (get "RedHat Linux Unleashed" if you can't find the particular one you want, since compatibility with RedHat seems to be the standard for most Linux OS versions).