What is the greatest invention in the 20th century? (1/2)

I believe the internet is the most important invention in the 20th century. There are two main reasons why I think so. One is the internet connects people in the world. The other is the internet provides various information for with us. First, using the internet enables us to easily communicate with each other around the world so that we are globally connected through the internet. For example, my graduate advisor said it was difficult for him to communicate with his family and relatives who live in Korea when he had studied abroad in the U.S. The only thing he could he could do was to call to them regularly and as paying expensive international calling fees. However, when I studied in the U.S. in 2007, I often communicated with my family for free through the internet. I called to them with face-time, emailed and communicated with them by using an instant messenger. So at that time, it only seemed like I lived in a distant area of from Seoul, but within Korea. Like this, the internet allows makes us to broaden our living boundaries to worldwide.