Moore's law is a specific example of a manufacturing learning curve, which can be described here: http://www.strategosinc.com/articles/strategy/learning_curve....

This is generally what people mean when they talk about "economies of scale": The more of a thing you make, the faster and cheaper you can make it. Moore's law (indirectly) names the constants on this curve for a integrated electronics, which is a field where the exponential relationship is more pronounced and continues over many more orders of magnitude than in most disciplines.