**Introduction:**

**Quantum physics** has opened new ways of research and development in the world of science like ultra high speed, immunity to eavesdropping, security etc. One such field is** Quantum Computing and Communication** where there is anything possible like you just name (process) it and it will be done (computed or communicated). Quantum computing makes the promise of solving issues that would be obstinate with conventional computers. It implements the principals of quantum physics in the development of computer hardware, software, and communication equipment. Quantum computers have the potential to perform certain calculations significantly faster than any silicon-based computer. Unlike digital electronic computers, quantum computers use **superposition** and **entanglement** to perform operations on data.

**Origin of Quantum Computing: **

Computers are around us from the very start of the 20th century but Quantum computing was first theorized less than 30 years ago by a physicist at the Argonne National Laboratory. **Paul Benioff** is credited with first applying quantum theory to computers in 1981. Benioff theorized about creating a quantum Turing machine so the Theoretical model of such computer is known as Quantum Turing Machine or Universal Quantum Computer. Scientists have already made basic Quantum Computers which can perform certain calculations but a practical quantum computer is still years away.

**Difference between Digital and Quantum Computing:**

**Digital or Classical Computers:**

Computers we use today are classical or Digital computers which store information in bits having **discrete value** either **0 or 1**. These operate on data including magnitudes, letters, and symbols. All the values are expressed in binary codes. There are certain problems which these computers cannot resolve e.g. think about caffeine molecule in a cup of coffee. No computer can be capable of modeling caffeine and fully understand its detailed structure and properties. Quantum computing has potential to tackle this type of tasks.

**Quantum Computers:**

Quantum computing uses the strange ability of subatomic particles i.e. to exist in more than one state at any time. Due to the way the tiniest of particles behave, operations can be done much more quickly and use less energy than classical computers. Taking the above example of caffeine in a cup, it follows the laws of** quantum mechanics** (a branch of physics that explores how the physical world works at the most fundamental levels). Particles behave in a strange way like taking one or more state at a time and interacting with other particles which are far away. Quantum computers are not intended to replace digital computers but they are expected to be a different tool which can solve very complex problems that are beyond the capabilities of classical computers.

**Quantum Computing and Communications:**

A book was published in **2005 **written by **Ferenc Balazs and Sándor Imre** named as **Quantum Computing and Communications. **This book gives details about the followings:

- Overview of basic quantum computing algorithms and their enhancement
- Introduces quantum-assisted solutions for telecom problems
- Includes an accompanying website featuring exercises (with solution manual) and sample algorithms.

**The Power of Quantum Computers:**

In the world of atomic and subatomic particles, things behave in an unexpected way as these particles can exist in more than one state at a time. It’s this ability that quantum computers take advantage of. Quantum computers use quantum bits (qubits) to store information; so the qubit can exist at any point of the sphere, unlike bit which is on any two sides of the sphere. “Qubit” can store a **“0” and “1”** simultaneously so If you build two qubits, they can hold four values at once —** 00, 01, 10, and 11**. So the computer can store an enormous amount of information with use of lesser energy. By entering the area of quantum computing; traditional laws of physics no longer apply. Scientists will be able to create processors that are significantly faster (million or billion times faster) than we use today.

The weird science of quantum computing, communications and encryption https://t.co/QJ6iR2CRHX

— Chuck Brooks (@ChuckDBrooks) June 28, 2017

**Advances in Quantum Computing:**

- A team of
**Google & NASA**scientists founded a**D-Wave Quantum Computer**last year which was**100 million times faster**than a classical computer. **IBM**has recently announced its**Q Division**in developing Quantum Computers and they expect to bring them to the market for commercial use and sale in coming years.