1. The place of nanodevices in the future International System of Units

World metrology is on the eve of a profound transformation with the change in the system of units. A major project is underway which will result in a system based on a limited number (≤ 5, probably) of fundamental constants. This idea is not new, and dates back to the end of the 19th century. It was pioneered by two eminent scientists. First, physicist George Stoney focused his research on the quantification of electric charge. In 1891, he officially introduced the term "electron" to describe the unit of electric charge. He even went so far as to estimate the value of this elementary charge. His contribution to research in this field paved the way for Thomson's actual demonstration of the electric particle a few years later. He quickly understood the importance of physical constants, and proposed the first attempt to define a system of units based on natural constants with :