It might be said that some of the most important advances of the 21^st century have been the iPhone, the iPod, YouTube and Skype. Today, they are a part of everyday life. The iPod and Apple’s music store, iTunes, (1) ... in 2001. The iPod’s modem design and large storage capacity made it very popular. And because of iTunes, digital music (2) ... normal. Skype has transformed the way people communicate across borders. Skype made it possible to call family or friends abroad  — and even video chat  — for free over WiFi. YouTube (3) ... in 2005 and is now the world’s most popular video-sharing website. Millions of hours (4) ... each month watching music videos, films, and even cat videos! Apple’s iPhone was the first user-friendly smartphone with a large touchscreen. It came out in 2007 and (5) ... over the mobile phone market, and a new industry was created  — app development. The 21^st century is still young. Who knows how our lives (6) ... by other inventions in the next few years!