Earth's changed over the years. And I'm not talking about the last decade. Or even the last century. For hundreds of millions of years, the surface of the Earth has slowly transformed from a few giant landmasses into the separated continents we have today. If you'd like to see this process in action, Ancient Earth, an interactive, time-travelling online globe, is a great place to start.
The globe, based on images and data from Christopher R. Scotese's PALEOMAP project, lets you view Earth in various states of change, going all the way back to 750 million years ago.
You can also jump to important points in time, such as the first appearance of multi-cellular life, primates and even grass, via a drop-down in the top-right.