What is difference between Linear and Logarithmic scale?

Linear graphs are scaled so that equal vertical distances represent the same absolute-dollar-value change. A drop from $10,000 to $9,000, for example, is represented in the same way as a drop from $100,000 to $99,000. The logarithmic scale reveals percentage changes. A change from 100 to 200, for example, is presented in the same way as a change from 1,000 to 2,000.