function explain {
  # base url with first command already injected
  # $ explain tar
  #   => http://explainshel.com/explain/tar?args=
  url="http://explainshell.com/explain/$1?args="

  # removes $1 (tar) from arguments ($@)
  shift;

  # iterates over remaining args and adds builds the rest of the url
  for i in "$@"; do
    url=$url"$i""+"
  done

  # opens url in browser
  open $url
}