The aim of this talk is not to introduce the specific research field in physics but to introduce the capability of particular experimental technique, angle resolved photoemission spectroscopy (ARPES), which is a widely utilized tool in the field of condensed matter physics. ARPES is the powerful technique that visualize the electronic structure of solid – how electrons are living in momentum space. It is a spectroscopy but can be also regarded as a momentum space microscopy. Not only just visualizing the electronic structure, ARPES provides deeper information on how electron lives, such as i) an interaction between electrons and other elements in solid, which is the source of various physic in solid, and ii) the symmetry and phase of the electron’s wave function that constraint the associated phenomena.

Starting from the basics of ARPES, the power of ARPES will be discussed and demonstrated with two recent research achievements of i) the evidence of interaction between electron and charge density wave excitation mode, and ii) visualizing the Berry curvature distribution of inversion symmetry broken system. Finally, the recent technical expansion of ARPES technique will be briefly reviewed to illustrate the scope of the research with ARPES.