Sophistication has advanced as people have learned new ways to develop various physical resources such as materials, forces, and energies. The history of computer technology has involved a series of changes in physical understanding, from gears and relays to valves, transistors and integrated circuits and so on. Today's advanced lithographic methods can squeeze a portion of micron-wide logic gates and buses onto the surface of silicon chips. Soon they will carry even smaller parts and eventually get to a point where logic gates will be so tiny that they will be built from a handful of atoms. At the atomic level, matter adheres to the rules of quantum mechanics, which are different from conventional rules. which govern the properties of orthodox logic gates. So, if computers are built smaller in the future, quantum technology must replace or improve what we have now. Quantum technology can offer much more than just transferring more bits to silicon and increasing the clock speed of microprocessors. It can support a completely new type of computing with advanced algorithms based on quantum principles. Quantum computing constitutes an important section of the new and rapidly evolving field of quantum information processing and communication. This field deals with representations and approaches to computing, algorithms, communication procedures, innate complexity considerations, cryptography protocols, etc., for situations where it is quantum, and not traditional, objects that are carriers of information.Research in quantum information processing it has already been proposed, compared to the traditional case, faster algorithms for certain important algorithmic problems, but not for all these problems; Fundamentally new cryptography... middle of paper...... extremely time-consuming on conventional computers. There are many difficulties that must be overcome before we can begin to appreciate the benefits they can bring. Researchers around the world are racing to be the first to build an applied system, a feat that some scientists say is futile. David Deutsch, one of the quantum computing scientists, himself said: "Perhaps their most profound effect could turn out to be theoretical." Can we really build a useful quantum computer? Who knows? in a quantum world, everything is possible! Works Cited “Quantum Computers”. ewh.ieee.org. ieee, and Web. November 7, 2011.< http://ewh.ieee.org/r10/bombay/news4/Quantum_Computers.htm>Gruska, Jozef. “Quantum computing”. Wiley Encyclopedia of Computer Science and Engineering (2009): March 16, 2009. Web. November 12, 2011.Smite-Meister. “Bloch_Sphere.” January 30. 2009.