Best Answer: To avoid all jargon (Experienced people please excuse the simplifications and omissions) :
Insulators are substances that do not conduct electricity very well.
Conductors are substances that conduct electricity readily.
A semiconductor is a man made material that can be made to conduct electricity at some times and not conduct at other times.
Using this behavior, semiconductors can be used to make devices that act as controllable switches, controlling the flow of a large amount of current with a smaller voltage or current. In this way, a small controlling voltage or current can be amplified to drive things such as speakers and motors.
A large number of these semiconductor switches (called transistors) can be built on tiny pieces of silicon and used perform calculations. These devices are the heart of every personal computer.
So in summary, semiconductors allow electricity to be used to perform just about all of the useful functions you see in everyday life.
Some prominent semiconductor companies are
Intel - the largest maker of Computer CPUs in the world
Texas Instruments - maker of the most popular electronic calculators and thousands of other semiconductors
Samsung - prominent Korean manufacturer of memory circuits and other electronics
Toshiba - large Japanese manufacture
Semiconductors are materials with a small amount of electrical conductivity. As a result, one can draw circuits on a semiconductor "wafer" by converting patterned areas on the surface to insulators and some areas to conductors. As a result, you can, using advanced photographic methods, grow an enormous amount of circuitry in a very small area.
The use of electronic devices like PCs and cell telephones in every day life has been expanding step by step thus the uses of semiconductors. Today, they are utilized in numerous gadgets and the standard of these gadgets is improving because of these semiconductors. There are compound and essential semiconductors. Both are utilized for distinctive purposes because of their specific attributes.
Light using so as to exude gadgets can be arranged semiconductors, similar to silicon. However, it is observed that a light utilizing so as to radiate gadgets made natural semiconductors are never as viable as the gadget made with a compound semiconductor. Silicon is by the by the most broadly utilized semiconductor substance and is for the most part utilized as a part of transistors and diodes. You can see them on all the electronic contraptions and circuit sheets. Furthermore, it is used in recollections and different parts of the PCs. It is even utilized in photograph sensors, radiation locators and strain gages.
Really, silicon is utilized as a part of about each electronic gadget found in the business sector. In the coming fifty years, the sunlight based cells are exceedingly liable to wind up extremely huge and crucial. Silicon is utilized in making sun based cells moreover. Semiconductors are used not just in electronic gadgets; they additionally act as an amalgam for a mixed bag of substances.
A compound semiconductor for the most part is more capable than a natural semiconductor. In this way, a large portion of the light radiating diodes are presently made utilizing the previous, for example, Gallium Arsenide. They transmit better light as well as give a wide assortment of hues; though LED is readied utilizing silicon as a rule can discharge just red, green or yellow light. Subsequently, LED is made utilizing compound semiconductors and is utilized for extremely tremendous screens at play areas or shows. Indeed, even these are utilized as a part of spot of customary radiant lights. Also they last more up to ten thousand hours when contrasted with eight hundred hours of a typical globule. With the onset of DVDs, these semiconductors have gotten a transformation the diversion business.
In general, semiconductors have turned into an a vital part of individuals' lives on the grounds that without mobiles, PCs, or other specialized gadgets our lives would be disabled.
This is too big a subject to put in a simple YA! answer an overview: a semiconductor is the basis of a logic circuit there are 6 main types of logic circuit NOT, AND, OR, NAND , NOR and XOR using these logic circuits, you can build adding circuits and multipliers
Just start from your cell phone and digital watches are made up of semiconductors only.
I am sorry there are many thousands of companies out of which prominent ones
Intel, IBM, AMD, Motorola, Texas Instruments, etc.