Explore the intricate structure of our nearest star in this comprehensive astronomy lecture. Delve into the Sun's interior, examining models and helioseismology techniques used to understand its composition. Investigate the solar neutrino problem and its implications for stellar physics. Examine the Sun's visible layers, including the photosphere, chromosphere, and corona, while learning about phenomena like limb darkening, spicules, and coronal heating. Analyze solar features such as sunspots, magnetic fields, and solar storms. Understand the sunspot cycle and the magnetic-dynamo effect that drives solar activity. Gain insights into the origin of the Sun's magnetic field and its impact on space weather.