Quantum mechanics is a fundamental theory in physics that describes the behavior of particles at the microscopic level. It is based on the observation that particles such as electrons and photons exhibit both wave-like and particle-like properties. This phenomenon is known as the wave-particle duality.

One of the key principles of quantum mechanics is the uncertainty principle, proposed by Werner Heisenberg. According to this principle, it is impossible to simultaneously determine certain pairs of physical properties, such as the position and momentum of a particle, with absolute precision. The more accurately we measure one property, the less accurately we can measure the other.

For example, let's consider an electron. If we want to precisely determine its position, we need to confine it within a small region by using a powerful microscope. However, the act of measurement disturbs the electron's momentum, making it impossible to know both its position and momentum with certainty. Hence, quantum mechanics introduces probabilistic predictions rather than deterministic ones. This probabilistic nature forms the basis of many quantum phenomena and applications in modern science and technology.

Quantum mechanics also introduces the concept of wavefunctions, mathematical functions that describe the probability distribution of a particle's properties. These wavefunctions can be used to calculate the probabilities of different outcomes when performing measurements on a quantum system, providing a powerful tool for understanding the behavior of microscopic particles.

In summary, quantum mechanics provides a fascinating framework for understanding the behavior of particles at the quantum level. It incorporates the wave-particle duality and the uncertainty principle, and its principles are described through mathematical entities such as wavefunctions. Understanding the concepts of quantum mechanics is crucial for delving into the exciting realm of quantum phenomena and their applications in various fields.