# Quantum Algorithms

**- Overview**

Quantum algorithms are procedures for solving computational problems. They are a set of instructions that use quantum properties to solve mathematical problems faster than a classical computer.

Quantum algorithms are usually described by a quantum circuit. A quantum circuit is a model for quantum computation where the steps to solve the problem are quantum gates performed on one or more qubits.

Quantum algorithms are different from quantum protocols. Quantum protocols are a set of standard rules that allow multiple devices to communicate.

Quantum algorithms can be used for applications such as breaking cryptographic systems and designing new medicines.

Please refer to Wikipedia: **Quantum Algorithm** for more details.

**- Well-known Quantum Algorithms**

Shor's algorithm is one of the most famous quantum algorithms. It was developed in 1994 by Peter Shor to find the prime factors of a given number. Shor's algorithm is exponentially faster than the best-known classical algorithms for factoring.

Another well-known quantum algorithm is Grover's algorithm, which is used to search an unstructured database or unordered list. Grover's algorithm is considered one of the most important quantum algorithms after Shor's algorithm.

Here are some other quantum algorithms:

- Variational Quantum Eigensolver (VQE): A hybrid quantum-classical algorithm that calculates the ground state energy of a molecule's Hamiltonian.

- Bernstein-Vazirani: Identifies a secret binary string in a single pass.

**- Techniques Used in Quantum Algorithms**

Some techniques used in quantum algorithms include:

- Phase kick-back
- Phase estimation
- The quantum Fourier transform
- Quantum walks
- Amplitude amplification
- Topological quantum field theory

Q# is a domain-specific programming language developed by Microsoft for expressing quantum algorithms. It is integrated with the .NET framework and can work with classical languages like C# and Python.

**[More to come ...]**