Laser cooling and trapping is one of my areas of research. This book represents a compilation of some of my recent work in this area. For example, figure 2.2 shows a CCD image of a cloud of trapped ytterbium atoms. The cooling and trapping is done using a combination of laser beams and a quadrupole magnetic field. The fluorescence from the atoms is at the cooling wavelength of 398 nm (resonance fluorescence), and hence the image is in real color of violet.