The discovery of the ferroelectricity of HfO₂ in 2011 has opened up new avenues for the application of ferroelectric technology. With the stability of ferroelectricity in a few nm scales, HfO₂ has become a valuable material for the development of next-generation electronic memory devices. The unique structure of HfO₂ gives rise to various ferroelectric properties and behaviors that can be utilized in different types of devices such as ferroelectric field effect transistors (FeFETs), negative capacitance field effect transistors (NCFETs), ferroelectric tunnel junctions (FTJs), and ferroelectric capacitors (FeCAPs). In this review, we explore the potential of HfO₂ for the high-density storage of data and low-energy consumption in next-generation devices. We demonstrate the operating principles and strengths of HfO₂ in various device applications, shedding light on how this material can help address the electronics industry's current challenges.