1. They're mixing a Bourne-ism (backquotes) with a Bash-ism (dollar-parens). I don't know why.

2. This could be an attempt to normalize and reduce whitespace, including eliminating newlines (though you should prevent injection of arguments to `echo`):

    bash$ Temp=$(echo "  a  b  c  ")
    bash$ echo "[${Temp}]"
    [  a  b  c  ]

    bash$ Temp=`echo $(echo "  a  b  c  ")`
    bash$ echo "[${Temp}]"
    [a b c]

    bash$ Temp=$(echo $(echo "  a  b  c  "))
    bash$ echo "[${Temp}]"
    [a b c]