What is qubit in quantum computing ?
In present day computing, we use 0 (Zeros) and 1 (Ones) to store and process data, think of it in terms of on off switch.
It is because computers can process data easily and quickly, if every information is represented in combination of 0 and 1.
Let us take an example of letter “a”, in English language “a” is simply a. However, in computing, letter “a” is represented as 01100001.
We can understand languages. It might seam easier for us to represent words and letters. But, computers have no understanding of languages. Sure we can program them but it will be a lot easier if we can standardize them. Hence, we utilize the simplest and most basic unit of information, which is 0 and 1.
This basic unit of information in 0 or 1, is called a Bit.
From data storage or CPU processing or even in communication, Bit is the fundamental building block of all data in classical computing.
What is Qubit ?
A Qubit or Quantum Bit is like a bit but used in a quantum system.
In classical computing, We can represent Bit with electrical signals, different voltages, present or not.
Similarly in quantum system, qubit, we can represent, with photon (number of photons or may be horizontal and vertical light), electron (spin up or spin down) and even with vibrational states.
Quantum system provides many different mechanics for the implementation in quantum computing.
So What is the difference between Qubit and Bit ?
A Bit can exists in two state, either 0 or 1.
However Qubit can have 0 or 1, also superposition where it is 0 and 1 at same time, with some probability of either 0 or 1.
This allows qubit in quantum computers to represent a exponential amount of data, hence huge increase in computing power.
