The geologic history of Earth covers more than 4.5 billion years. Different types of phenomena and events in widely separated parts of the world have been correlated using an internationally acceptable, standardized time scale. The layouts presented by EdrawMax are 100% customizable, and you can edit them as per your requirement. Timelines can use any suitable scale representing time, suiting the subject and data; many use a linear scale, in which a unit of distance is equal to a set amount of time. As illustrated in the below timeline, a Geologic Time Scale is the history of the Earth broken down into four spans of time marked by various events, such as the emergence of certain species, their evolution, and their extinction, that help distinguish one era from another.