### The Present Context

- Google has officially claimed that
**they have achieved quantum supremacy.** - Google claims that they
**are able to build a quantum computer**that is**able to solve complicated in just 200 seconds that take the world's fastest supercomputer 10000 years.** - This computer is
**a 54 qubit**( qubit is explained later in this article) computer. - However,
**this claim of google is challenged by IBM.**

**Quantum Computer: **A **quantum computer is a computation system that makes direct use of quantum-mechanical phenomena.**

### Classical computing and classical bits

- Classical bits: The basic component of a classical computer is the bit(a single binary variable values of 0 and 1)
- A classical computer
**uses binary bits(0s and 1s) for the process of computing.** - The classical
**computer**can**exist in only one stage at a given instance.**However,**they have 2^n combinations of states.** - The
**stage of a classical computer is described by some long combinations**of 0s and 1s. Ex: 000011110000101010........ - For example, a
**32-bit computer has 2^32 stages but can exist in only one stage a given instance.**

### Origin of Qubit and Schrodinger's Cat thought experiment

- Schondrigner imagined
**a box inside which there is a cat and there is also a flask of poison**. - The flask of poison has to be
**opened by an automatic trigger that has been placed inside the box.** - When the flask will open
**the poison is going to kill the cat.** - But
**for an external observer,**there is**no way to know when the trigger is opening the flask and going to kill the cat.** - The only way to know the condition of the cat is to
**open the box,****so for the external observer, the cat is appeared to be both dead and alive at the same time.** - This
**originates the concept of quantum superposition and qubit which can store more than one stage at an instance**.

### Quantum Computing and qubits

- Science students may know that
**a part of Quantum Physics deals with multiple behaviors of the electron, and photons at a given time.** - Quantum computers use
**Q****ubits for the process of computing. Here Qu in Qubits stands for Quantum.** - The main difference between bit and qubit is that
**the qubit allows quantum computers to occupy 2^n(n is the number of qubits) stages at a given instance which makes the quantum computing exponentially faster than classical computing, while the bit allows a classical computer to occupy only one stage at a given instance.** - The property of
**quantum computers to occupy multiple stages at any instance of time is known as Quantum Superposition.**