https://purengom.com/2008/12/31/%eb%8b%b9%ec%8b%a0%ec%9d%b4-%eb%a7%8c%ec%95%bd-apple%ec%9d%84-%eb%af%bf%eb%8a%94%eb%8b%a4%eb%a9%b4-%ec%b5%9c%ea%b3%a0%ec%9d%98-%eb%af%b8%eb%94%94%ec%96%b4-%ed%94%8c%eb%a0%88%ec%9d%b4%ec%96%b4-ipod-tou/