1. Observations of stars. 1.1. Locations of stars. 1.2. Stellar material. 1.3. Determining the distances of stars. 1.4. The temperature of stars. 1.5. Stellar radii. 1.6. Estimating stellar masses. 1.7. The physical properties of main-sequence stars. 1.8. Stellar spin rates 1.9. Summary -- 2. Producing protostars - embryonic stars. 2.1. Star-forming regions. 2.2. The formation of dense cool clouds. 2.3. Maser emission from star-forming regions. 2.4. The process of protostar formation. 2.5. The formation of binary systems. 2.6. Modelling the collapse of a cloud. 2.7. The spin of stars. 2.8. Summary -- 3. The life and death of a star. 3.1. The journey to the main sequence. 3.2. Energy generation in main-sequence stars. 3.3. Leaving the main sequence for low and moderate-mass stars. 3.4. The evolution of higher-mass stars. 3.5. Summary -- 4. The evolution of a galactic cluster. 4.1. Embedded clusters. 4.2. The formation of massive stars. 4.3. The embedded cluster environment and binary star frequencies. 4.4. The progress of star formation in a galactic cluster. 4.5. Summary -- 5. Exoplanets - planets around other stars. 5.1. Planets orbiting neutron stars. 5.2. The characteristics of orbits. 5.3. Planets around main-sequence stars; doppler-shift detection. 5.4. The direct imaging of exoplanets. 5.5. Exoplanets and the solar system. 5.6. Summary -- 6. The formation of planets: the capture theory. 6.1. The interaction of a star with a protostar. 6.2. The interaction of a star with a high-density region. 6.3. Summary -- 7. Orbital evolution. 7.1. The nature of the disk. 7.2. The force on a planet due to the medium. 7.3. Modelling the medium and details of the calculation method. 7.4. Calculations of orbital decay and round-off. 7.5. Orbits of high eccentricity. 7.6. The range of semi-major axes. 7.7. Simple ratios of orbital periods. 7.8. Stellar spin axes. 7.9. Summary -- 8. The frequency of planetary systems. 8.1. observations and observational constraints. 8.2. Initial formation statistics. 8.3. The disruption of planetary systems. 8.4. Summary -- 9. Satellite formation. 9.1. Angular momentum considerations. 9.2. The form of the disk. 9.3. The settling of dust. 9.4. The formation of satellitesimals. 9.5. Satellite formation. 9.6. Comments. 9.7. Summary