Includes supplementary material: [...]

1. Characteristics of the Sun.- 1.1 Distance.- 1.2 Mass.- 1.3 Radius.- 1.4 Luminosity.- 1.5 Spectral Energy Distribution.- 1.6 Bibliographical Notes.- 2. Internal Structure.- 2.1 Construction of a Model.- 2.2 Age and Pre-Main-Sequence Evolution.- 2.3 Model Ingredients.- 2.4 Results for a Standard Solar Model.- 2.5 Non-Standard Models.- 2.6 Bibliographical Notes.- 3. Tools for Solar Observation.- 3.1 Limitations.- 3.2 High-Resolution Telescopes.- 3.3 Spectrographs and Spectrometers.- 3.4 Filters and Monochromators.- 3.5 Polarimetry.- 3.6 Special-Purpose Instruments.- 3.7 Bibliographical Notes.- 4. The Atmosphere.- 4.1 Radiative Transfer - Local Thermodynamic Equilibrium.- 4.2 Radiative Transfer - Statistical Equilibrium.- 4.3 Atmospheric Models.- 4.4 The Chemical Composition of the Sun.- 4.5 Bibliographical Notes.- 5. Oscillations.- 5.1 Observations.- 5.2 Linear Adiabatic Oscillations of a Non-Rotating Sun.- 5.3 Helioseismology.- 5.4 Excitation and Damping.- 5.5 Bibliographical Notes.-6. Convection.- 6.1 Stability.- 6.2 Mixing-Length Theory.- 6.3 Granulation.- 6.4 Mesogranulation.- 6.5 Supergranulation.- 6.6 Giant Cells.- 6.7 Bibliographical Notes.- 7. Rotation.- 7.1 Axis of Rotation.- 7.2 Oblateness.- 7.3 Rotational History.- 7.4 The Angular Velocity of the Sun.- 7.5 Models of a Rotating Convection Zone.- 7.6 Bibliographical Notes.- 8. Magnetism.- 8.1 Fields and Conducting Matter.- 8.2 Flux Tubes.- 8.3 Sunspots.- 8.4 The Solar Cycle.- 8.5 Bibliographical Notes.- 9. Chromosphere, Corona, and Solar Wind.- 9.1 Empirical Facts.- 9.2 Consequences of High Temperature.- 9.3 The Magnetic Field in the Outer Atmosphere.- 9.4 The Energy Balance.- 9.5 Explosive Events.- 9.6 Bibliographical Notes.- List of Symbols.- References.