This first chapter aims to introduce the topic of financial literacy by providing and explaining the main definitions and analyzing the meaning and the different components of financial literacy. Subsequently, the chapter reports general evidence of the level of financial literacy all around the world, available from international survey data such as OECD and World Bank surveys, and descriptive analyses of the distribution of financial literacy among different sociodemographic categories, showing gaps related to gender, education, geographical origin, and income. Finally, the chapter provides an overview of the actors with key roles for the general development of financial literacy in society, such as governments, supervisory authorities, educational institutions, and financial intermediaries, analyzing their contribution in spreading financial education in the society.