In this video Prof. Rosling shows that people live in very different income levels. The poorest live in less than 1 dollar a day. Many people live with 10 dollars a day, while other live with 100 dollars a day.
There are around 1 billion people in the world who live with less than 1 dollar per day. More than half of the world population lives with less than 10 dollars a day. And some people live with more than 100 dollars per day.
There are huge differences in income between the richest and the poorest. Referring to this difference as a gap in income gives the impression that there are only extremely rich or extremely poor people. In reality, the majority of the world population lives in between.
The Changing Shape of Global Inequality – exploring a new data set (2011), by Jan Luiten van Zenden & others; https://goo.gl/r1fgGw.