Nowadays, the quality of life has greatly improved, particularly in terms of access to services. However, heavy industrialization and the increasing population in the urban areas have been a big challenge for administrators, architects, and planners. For this reason, the transformation of metropolises into smart cities is a crucial factor in improving the living conditions of their inhabitants. Despite the popularity of the phrase "smart city," there is still misunderstanding about its meaning, especially since several similar terms are often used. This paper aims to clarify the meaning of the word "smart" in the context of cities through an approach based on an in-depth literature review of relevant studies. It also identifies the main dimensions and elements defining the smart city. In addition, it demonstrates how we can consider a particular city a smart one, drawing on recent practises to make cities smart.