Commands--examples: First, log on as root, then run ./install--or--./install --prefix/usr--or--./install --gzip, etc. Another example: run this command-- - sh z35cups-1.0-1.tar.gz.sh--to install Lexmarkz25/35 driver. Does "run" mean "type?" because that is what I do. I know the basic commands of current directory, change directory, list, file, less, and a few more. I always know the directory I'm in or the directory the file I want to run is in. I know how to get into root when I'm instructed to. I really need help conceptuallizing this command system. Please help.

sh is the command to run i.e. execute a shell script. The shell script being the z35cups-1.-.....tar.gz.sh file. File extensions like .com do not have any meaning in linux however there are some that are used for naming conventions. sh for shell scripts and .conf for configuration files are but a couple. Thats not the only way to execute a shell script. If you set its permissions for excute you can 'run' the script by just typing in its name like
./name. The command chmod changes a files permissions.

The ./ is a short cut for current working directory. Unlike windows the environment path does not automatically include the current working directory. The command:
echo $PATH

Will display the current users enviroment path variable.

I assume that ./install is just another special install script for a particular application your trying to install. gzip is the application that zips and unzips files just like the DOS/windows versions.

A shell script is similar to a batch file in DOS or windows but 100x more powerfull. The console text window is also known as a shell and the ususal installed shell is BASH i.e. Borne Again Shell. The linux shell has lots of commands. Just search the web for info or run down to your local library or Barns and Noble and browse the bookshelfs on linux books. You will find some on the BASH shell and shell programming.

The command system is basically no different than the old DOS command prompt except it works 1000x better. The commands can be cryptic sometimes but you will catch on quickly. You have shell internal commands and external applications. If the command isn't in the path variable then either type in the whole path to the command or change the path variable to include that commands directory locations. The man pages has basic help files for a particular command ie

man chmod