My father is an engineer of old hardening. Svokor is an engineer of a slightly newer hardening (he is ten years younger). My husband is a modern programmer. One day at a family feast there was a conversation about light bulbs, bulbs and energy savings. It turns out that there are three big differences. Because the father begins to draw a scheme, it is easier for the mother-in-law to merge a demonstration sample and measure with a tester, and the husband began to compose a script so that he could count.