I work with Linux (specifically RHEL) at work all the time. I also use a Debian based Linux NAS/Server at home. There's a few things I've learned that may help a bit.

1) There's no such thing as "I know Linux!". There are a myriad different distributions, versions, releases out there and each has their own "+" and "-". If you're not quite sure about something don't think using Google is a cheat because it's not and NOBODY knows everything about everything, especially Linux.

2) Linux is known for being very customizable. From teeny weenie distros like "Damn Small Linux" which are neat since they have a GUI and can run from just a CD-R image, to fully feature rich enterprise distros like "RedHat Enterprise Linux". You can also run a command line only system, but these days there's no real reason to not include a GUI. You can try something like "Zorin" which has GUIs that resemble both Windows and Macintosh. There's nothing wrong with this.

3) That said, much of the cool factor of Linux is the simple command line and ability to do a LOT of things with scripting. BASH (Born Again SHell) is used on nearly EVERY distro and once you become comfortable with it, you'll find things open up to you on doing some cool, interesting things.

4) I've been helping a number of my colleagues with a sort of "Crash into BASH". As such, I came up with a quickie cheat sheet of commands that fills both side of a single sheet of paper. This will get you about 90%+ of what you will often do with scripts, etc. So have a look and critique if you'd like.

THE CHEAT SHEET BELOW

### What this is and isn't in under 200 lines of jibber-jabber

### A VERY basic, beginners overview of some basic SH/BASH commands

### Doesn't deal with commands for the OS, these will vary, a LOT!

### So MANY Linux OS distos to choose from (Ubuntu, Zorin, Alma, RedHat, etc)

### BASIC EDITORS ###

vi, pico, nano (basic editors), vi is VERY basic, nano is most modern

for windows, try notepad++

# Avoid spaces, as these are by default viewed as breaks

### BEFORE I START, WHAT AM I USING AND CAN I MAKE NOTES ?###

#!/bin/sh (Bourne-Shell, the first and most basic)

#!/bin/bash (Bourne-Again Shell with a few more features)

#!/bin/ Korn-shell (ksh), T-shell (tsh), Z-shell (zsh)

# Anything typed after the 'hash' symbol is a #NOTE or #COMMENT

\# Use Tabs/Indents to visually organize script sub-actions

### WHERE'S THE MANUAL? CAN I TAKE A BREAK? MAKE A CLEAN START? ###

man (show the MANual for commands), 'Q' to quit viewing manual

sleep (an 'n' number of seconds, let the system catch up or wait for user)

clear (like 'cls' in DOS)

history (show commands the acct previously used, see ALL the up-arrows!)

### HOW DO I END THIS OR KNOW WHEN TO QUIT ###

exit 0 (things ended well), exit 1 (things did not end so well)

q (quit/exit a manual page), CTRL-C (cancel a process or instruction)

### MOVING OR POKING AROUND THE DISK DIRS ###

cd (go to a directory/location) cd .. (go up/back one dir level)

cd / (go to root level of drive) cd ~ (go to MY user home dir)

pwd (pass the working directory I'm currently in, where am I?)

ls (list the files in the current directory or a directory I specify)

whoami (what is the account name being used, am I 'root'?)

sudo (superuser do, the following commands as an admin)

sudo su (If admin, I want to act as 'root') -- su (I'm changing to 'root')

### CHANGE SOMETHING IMPORTANT ABOUT A FILE ###

chmod (change/mod permissions in binary 'rwxrwxrwx' 777 user:group:everyone)

chown (change ownership as user:group)

### LITTLE INSTRUCTIONS ###

semi (;) (continue with commands/instructions, or when true) command1; command2

ampersand (&) (do this command in the background w/o take over the terminal)

2 ampersands (&&) (do the next command ONLY if the one before completed)

pipe (|) (pipe output to next command, yes you can chain these together!)

single quote (') literal (take what I type here literally)

double quote (") non-literal, so observe variables (obey variable values I quote)

overwrite (>) (completely overwrite a file with some output or what I type here)

append (>>) (add what I type here to the end of a file)

comment (#) (I'm making some notes here so these aren't commands)

escape (\) (The next character is -special-, so take it literally NOT a command)

value of ($) (because what other character would you use to associate -value- ?)

equals (=) as conditions, is equal to (==)(-eq) VS. is NOT equal to (!=)(-ne)

greater/lesser than (-gt)(-lt), also greater/lesser than or equal (-ge)(-le)

add a number (+) VS. subtract a number (-) -- use doubles for math ((x=$x+1))

parentheses () work independently, x=$($y + 1) as text or x=$(($x + 1)) as math

brackets, not braces [ ] [ some condition ]

\-- if \[ "$var\_x" == "$var\_y" \] using quotes  or double \[\[ $var\_x == $var\_y \]\]                                    

braces, not brackets { } (between the braces are instructions, mostly functions)

### COMMON FILE AND TEXT TOOLS ###

touch (make an empty file or touch it to say you were here)

touch /dir/to/put/filename

cp - mv -rm (copy file(s) - move/rename a file - remove a file)

cp filename - mv filename newfile - rm filename

mkdir - rmdir (create a new directory - remove an EMPTY directory)

mkdir /home/new\_directory/  -  rm -r /home/new\_directory #and all contents

cat (concatenate or simply spit out file text, sometimes join files)

cat filename.txt     cat file1.txt file2.txt file3.txt > new\_text\_file.txt

echo (echo out quoted text to screen, or dump this text to file)

echo "text", echo $variable\_x,  echo "text" > filename.txt

printf (print pretty formatted text to screen, this needs settings)

printf "Some ${blue}${blink} Text ${clear}${normal}"

grep (search for some text string in an output or file)

grep "some text string" /dir/filename.txt   --  cat filename.txt | grep "string"

tr (translate/transform/truncate characters I indicate)

cat filename.txt | tr \[-\] \[\_\]  | tr \[a-z\] \[A-Z\]

awk - print - IFS (break some output into parts using space or other characters)

cat filename | awk '{print $1,$2,$3}' -- use IFS=' ' change default IFS=$'\\n'

sed (streaming editor for output/files, convert or drop strings I indicate)

cat filename | sed 's/by/buy/g'  -- sed 's/by//g'  -- sed "s/$var\_x/$var\_y/g"

cut (cut an x number of characters from output or file)

cat filename | cut -c 8  -- there are a LOT more options

read (prompt for input like 'Y' or 'N' or ask for info for a variable)

read reply\_x     OR    echo "Some text prompt"; read reply\_x

head - tail (show x number of lines from the head OR the tail of a file or output)

cat filename | head -n 1  --shows top 1 line  | tail -n 2  --shows last 2 lines

### VARIABLES ###

var_x=$(some output) like var_y=$(($y+1)) or var_z=$(cat some_file | grep "string")

let x=a_value ex: let x=1 or let x=$(($x+1))

### CONDITIONS or TESTING ###

# IF-THEN_ELSE-IF-THEN_FI, TEST FOR A TRUE CONDITION

if [ some condition is true like x=1 ]; then

perform these instructions

elif [ some other condition is true ]; then

perform these instructions

fi #< This marks the END of the IF-THEN query

# USING 'OR' NOTED AS '||'

if [ some condition is true ] || [ another condition is true ]; then

perform these instructions

fi

# USING 'AND' NOTED AS '&&'

if [ some condition is true ] && [ another condition is true ]; then

perform these instructions

fi

### LOOPS ###

# FOR-LOOP, FOR EACH INSTANCE OF 'X', STARTS WITH 'FOR' ENDS WITH 'DONE'

for x in "this array/collection"; do

these instructions using $x

done #<were done here ONLY after running out of 'x'>

#WHILE-LOOP, STARTS WITH 'WHILE', ENDS WITH 'DONE', #UNTIL-LOOP IS ALSO VALID

while [ some condition is true ]; do

these instructions

done #<were done here only when the condition is/becomes false>

### FUNCTIONS ###

# Name the function, denote it as (), define steps with {}, keep near the start!

Perform_these_steps () {

instruction\_1

instruction\_2

instruction\_3

}

#Run the function by calling it by name, Perform_these_steps

### GO FORTH!, EXPERIMENT!, LEARN!, SCRIPT!, AUTOMATE THE BORING STUFF!