Geologic time is a very difficult concept for humans to grasp because of it's sheer magnitude.
A million years is a very, very long time in human terms. The Earth was formed 4,500 million years ago. Very early complex life forms first began to flourish 550 million years ago at the beginning of the Cambrian Period. One million years ago, man first began to fashion VERY crude pebble tools. Please click another colored block to learn more about Earth's history.