Some bash conventions as an example

myBashTemplate.sh

#!/bin/bash
##################################################################################
##                        A NOTE ABOUT YOUR SCRIPT                              ##
##################################################################################
VARIABLE="MyString123"
FILE_NAME="${VARIABLE}.txt"
EMPTY_ARRAY=()
COMMAND_OUTPUT=$(echo $VARIABLE) #MyString123
BACK_TRIMMED_VARIABLE=${VARIABLE::(-1)}; #MyString12
FRONT_TRIMMED_VARIABLE=${VARIABLE:(1)}; #yString123
TO_UPPER=$(echo $VARIABLE | tr [a-z] [A-Z]) #MYSTRING123
TO_LOWER=$(echo $VARIABLE | tr [A-Z] [a-z]) #mystring123
#Multiple string array
LIST_ARRAY=(
  'My'
  'String'
  '123'
  '4'
)

#A simple function to print areguemnts. called with print_arguments someString someOtherString
function print_arguements()
{
  local FIRST_ARG=$1
  local SECOND_ARG=$2
  printf "My first argument is $FIRST_ARG. My second arguemet is $SECOND_ARG"
}
print_arguments foo bar #"My first argument is foo. My second arguemet is bar"

#For loop for all items in an array
for item in ${LIST_ARRAY[@]}
do
  printf "$item\n"
done

#Split values by comma
ITEMS="foo,bar"
IFS="," PARTS=( $ITEMS )
FOO="${PARTS[0]}" #foo
BAR="${PARTS[1]}" #bar

#Add something to your EMPTY_ARRAY
EMPTY_ARRAY=()
EMPTY_ARRAY=(${EMPTY_ARRAY[@]} stuff)
EMPTY_ARRAY=(${EMPTY_ARRAY[@]} things)
printf "Your Array isn't so empty. We put %s and %s in it." ${EMPTY_ARRAY[@]}

#Check Internal Field Separator
echo $IFS | cat -A

#Write out a multiline file with variables in it
cat >> ~/$FILE_NAME << EOL
line 1
line 2
/variable/in/a/path/${VARIABLE}.txt
$COMMAND_OUTPUT
EOL
#If a file exists - it should because we made it in the step above
if [ -f ~/$FILE_NAME ]
    then
        #cat file
        cat ~/$FILE_NAME
    else
        #Say the file doesn't exist
        printf "$FILE_NAME doesn't exist!\n"
fi
#A case statement
case $VARIABLE in
MyString123)
  Message="Variable is MyString123"
  ;;
*23*)
  Message="Variable contains 23"
  ;;
*)
  Message="Variable wasn't MyString123 or *23*"
  ;;
esac