####   linuxcommand.org is good starting point######
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command:		do:
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pwd			where are you
ctrl c			terminat script/command
q			quit man
clean			clean the terminal
reset			reset the terminal
man <>			manual page 
cat\less\more <>	print file to std
nano/gedit <>		text editor
ps -a -A		id# of running processes.
top			processes that run and the user
chmod <>		r-4/w-2/x-1 change premission
chown user <>		change owner
kill -9	id		stop process
killall			stop all process
wildcard		*?
***ls (-ltr)		list of file\dir
***cp (-r) <>		copy (folder)
***mv <>		move file or file name
***cd <>		change dir
file			examine a file type
|more			after  command to disply all the  file
rm (-rf) <>		remove file (folder !!!!)[if use with wildcard do ls befor rm]
rmdir <>		remove dir
mkdir <>		make new dir
locate <>		find
&\^z-->bg		after command to run it in bg
dorsquota |grep user 	total storage size on DORS
du -sh (-a) <>		used vol (all files)
 | 			pipe line of commads
 >			send output to...
 >>			send output to... without over write
 >&			send output and error output to...
 <			use stdin form...
`  ` or $( )		command substitution - executed first and use as a input


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filters:		do:
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sort			sort input 
uniq			removes duplicate data 
grep			find and output match to a given pattern
fmt			output formatted the text
pr			prepare for printing
head			output the start of file
tail			output the edn of file
tr			
awk			
echo			


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bash var:
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set var --> var_name=some_input
$var equal the input
1.    $1, $2, $3, ... are the positional parameters.
2.    "$@" is an array-like construct of all positional parameters, {$1, $2, $3 ...}.
3.    "$*" is the IFS expansion of all positional parameters, $1 $2 $3 ....
4.    $# is the number of positional parameters. 
5.    $- current options set for the shell.
6.    $$ pid of the current shell (not subshell).
7.    $_ most recent parameter (or the abs path of the command to start the current shell immediately after startup).
8.    $IFS is the (input) field separator.
9.    $? is the most recent foreground pipeline exit status.
10.   $! is the PID of the most recent background command.
11.   $0 is the name of the shell or shell script.


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programs:
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1.xv			print screen
2.okular		pdf viewer
3.nano/gedit/emacs	text editor
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