https://itmanual.net/macos-%eb%a7%a5%eb%b6%81-%ea%b3%b5%ec%9d%b8%ec%9d%b8%ec%a6%9d%ec%84%9c-%ec%9c%84%ec%b9%98-%eb%a7%a5%eb%b6%81-%ea%b3%b5%eb%8f%99%ec%9d%b8%ec%a6%9d%ec%84%9c-%ec%9c%84%ec%b9%98-1%eb%b6%84%eb%82%b4/