With each technological ‘revolution', more energies began to be accessed, stored, and used than had been in the preceding epoch...On the whole, technological change is irreversible: whatever the nature of a technological revolution, it is always from the hoe to the plough, and not the other way around...Improvement generally means greater efficiency in the use of energy, materials, or information. It means greater speed, less investment of time and money, and operation on a larger scale.