echo $identifier_azAZ09
echo $Identifier_azAZ09
echo $_identifier_azAZ09
echo $0
echo $1
echo $2
echo $3
echo $4
echo $5
echo $6
echo $7
echo $8
echo $9
echo $@
echo $*
echo $-
echo $# # Expands to a number
echo $? # Expands to a number
echo $$ # Expands to a number
echo $! # Expands to a number

echo ${identifier_azAZ09}
echo ${Identifier_azAZ09}
echo ${_identifier_azAZ09}
echo ${identifier_azAZ09}a
echo ${Identifier_azAZ09}a
echo ${_identifier_azAZ09}a
echo ${identifier_azAZ09}"a"
echo ${Identifier_azAZ09}"a"
echo ${_identifier_azAZ09}"a"
echo ${identifier_azAZ09}"/a"
echo ${Identifier_azAZ09}"/a"
echo ${_identifier_azAZ09}"/a"
echo ${identifier_azAZ09}${identifier_azAZ09}
echo ${Identifier_azAZ09}${Identifier_azAZ09}
echo ${_identifier_azAZ09}${_identifier_azAZ09}
echo ${0}
echo ${1}
echo ${2}
echo ${3}
echo ${4}
echo ${5}
echo ${6}
echo ${7}
echo ${8}
echo ${9}
echo ${1}0
echo ${10}
echo ${@}
echo ${-}
echo ${#} # Expands to a number
echo ${?} # Expands to a number
echo ${$} # Expands to a number
echo ${!} # Expands to a number

echo ${#array[@]} # Expands to a number
echo ${array[0]}
echo ${array[@]}
echo ${array[*]}
echo ${subst##*/}
echo ${subst#*/}
echo ${subst%/*}
echo ${subst%%/*}

echo "$identifier_azAZ09"
echo "$Identifier_azAZ09"
echo "$_identifier_azAZ09"
echo "$0"
echo "$1"
echo "$2"
echo "$3"
echo "$4"
echo "$5"
echo "$6"
echo "$7"
echo "$8"
echo "$9"
echo "$@"
echo "$*"
echo "$-"
echo "$#" # Expands to a number
echo "$?" # Expands to a number
echo "$$" # Expands to a number
echo "$!" # Expands to a number

echo "${identifier_azAZ09}"
echo "${Identifier_azAZ09}"
echo "${_identifier_azAZ09}"
echo " ${identifier_azAZ09}"
echo " ${Identifier_azAZ09}"
echo " ${_identifier_azAZ09}"
echo "${identifier_azAZ09} "
echo "${Identifier_azAZ09} "
echo "${_identifier_azAZ09} "
echo "${identifier_azAZ09}${identifier_azAZ09}"
echo "${Identifier_azAZ09}${Identifier_azAZ09}"
echo "${_identifier_azAZ09}${_identifier_azAZ09}"
echo "${0}"
echo "${1}"
echo "${2}"
echo "${3}"
echo "${4}"
echo "${5}"
echo "${6}"
echo "${7}"
echo "${8}"
echo "${9}"
echo "${1}0"
echo "${10}"
echo "${@}"
echo "${*}"
echo "${-}"
echo "${#}" # Expands to a number
echo "${?}" # Expands to a number
echo "${$}" # Expands to a number
echo "${!}" # Expands to a number

echo "${#array[@]}" # Expands to a number
echo "${array[0]}"
echo "${array[@]}"
echo "${array[*]}"
echo "${subst##*/}"
echo "${subst#*/}"
echo "${subst%/*}"
echo "${subst%%/*}"