The Nobel prize in chemistry has been awarded to the click chemistry approach in 2022 due to its significant impact on nearly all fields of chemical science. The present review describes one of these reactions, the Cu(I)-catalyzed alkyne–azide cycloaddition (CuAAC) reactions as a powerful fluorogenic tactic for sensing and bioimaging of diverse biomolecules. Imperative features of click chemistry will be presented, including the concept and the criteria of a click reaction, the mechanism of CuAAC, the catalysts used and the different reaction conditions. In addition, this review highlights the synthesis of a variety of fluorogenic 1,4-disubsituted triazoles with different core structures from azide and terminal alkyne using fluorogenic CuAAC reactions and their major applications. In the end, we hope that this review will help readers learn more about different aspects of click chemistry and also motivate synthetic chemists to apply click chemistry in ever more creative and ambitious ways in different domains of scientific research.