Exponential Growth - from Wolfram MathWorld

Exponential Growth.

Exponential growth is the increase in a quantity according to the law. for a parameter and constant (the analog of the decay constant), where is the exponential function and is the initial value.

Exponential growth is common in physical processes such as population growth in the absence of predators or resource restrictions (where a slightly more general form is known as the law of growth). Exponential growth also occurs as the limit of discrete processes such as compound interest. Exponential growth is described by the first-order ordinary differential equation.