Microchips.

Microchips.

The first computers used components called valves. If you are very young, it is likely you have never seen
anything. The valves are no longer used in electronic equipment, except those found in enormous
PC monitor and TV screen.

The valves functioned as electronic keys. When the current passing through a portion of the tube, so that the heated
another component that electrons boiled and were attracted to the part of the valve that had a positive charge. Within
valve was required partial vacuum for the electron little resistance met molecules in the air. When
electrons move, the key is connected. When they were not floating, the switch remained off.

Basically, the computer is composed of a collection of on / off switches that, at first glance, seem unlikely to
usefulness. But imagine a large chain of lamps - say ten rows of fifty bulbs, totaling five hundred.
Each lamp is connected to a light switch. If you connect the right combination of lamps, can make the
letters of his name appear in lights.

Computers are very similar to this group of lights, with a basic difference. The computer can identify which
lights are on and use this information to trigger the other keys. If the sequential pattern of keys connected display
the word Bia, the computer can be programmed to associate the standard Bia the instructions that bind another key group
to spell it. If the pattern spelled Tom show, the computer can connect a different set of keys to show it.
The dual concept mapping on / off perfectly blends with the binary number system, which uses only 0 and 1
to represent all numbers. Working in rooms full of valves, the old computer engineers could
do mathematical calculations and binary, alphanumeric associating certain numbers could manipulate text.

The problem of these early computers was the intense heat generated by the hundreds of valves, making them somewhat
reliable. The heat meant that several components deteriorate and consume lot of energy. In
Indeed, for the valves to be connected, it was necessary to create this huge stream of electrons. A small enough
stream, but the valves were very large. Worked on a human scale and each part could be seen with the naked eye. They were
rudimentary and could not produce a smaller flow of electrons. The transistors have changed the way of designing
computers.

A transistor is basically a type of valve that does not work on a human scale, but microscopic. By presenting small
size, requires less energy to generate the flow of electrons. Because it uses less power, generates less heat, taking
computers more secure. Moreover, the microscopic scale of transistors enabled computer, previously occupied
an entire room, accommodating up perfectly on a desk.

All microchips - they are microprocessors, memory chips, or dedicated integrated circuit - are great
standardized sets of transistors to perform different tasks. Typically, the number of transistors that
can be created in a single chip is about 1.5 million. This physical limitation is caused by the precision index
(And miniaturization) that manufacturers can direct the light beams used to delineate (for process
corrosion with fatty) components of the transistor, which are made of materials sensitive to light. Manufacturers
chips are testing x-ray instead of ordinary light, because the X-ray is much narrower. One day, the transistors may
reaches its perfection - the molecular level - in which the presence or absence of only one electron signal the condition
on or off.

Source: Evolution of Computers