This lecture delves into the fundamental concepts of quantum science, focusing on the electron. It begins with the historical context of quantum mechanics, discussing the dual nature of particles, particularly electrons and photons. The instructor explains the wave-particle duality, highlighting the relationships established by Planck and de Broglie. The lecture covers the wave function and the Schrödinger equation, emphasizing their significance in describing electron behavior. The double-slit experiment is presented as a key demonstration of electron interference, illustrating how electrons exhibit wave-like properties. The discussion extends to the mathematical formulation of quantum mechanics, including operators and Hamiltonians, which are essential for understanding quantum systems. The lecture concludes with practical examples, such as the propagation of electrons in a vacuum and their implications in technologies like electron microscopy. Overall, this lecture provides a comprehensive overview of the electron's role in quantum science, bridging theoretical concepts with experimental evidence.