This article provides a comprehensive review of hydrogels, focusing on their preparation, characterization, and applications. Hydrogels are polymeric materials with a hydrophilic structure that can hold large amounts of water in their three-dimensional networks. The review highlights the transition from natural to synthetic hydrogels due to their higher water absorption capacity, longer service life, and availability of raw chemical resources. It discusses the technological aspects of hydrogel production, including various synthesis methods such as bulk, solution, and suspension polymerization, as well as radiation-induced polymerization. The article also covers the classification of hydrogels based on their sources, polymeric composition, configuration, cross-linking, and electrical charge. Additionally, it explores the technical features and process design implications of hydrogel production, emphasizing the optimization of parameters for bead yield, smoothness, sphericity, and clarity. The review further delves into the preparation of specific hydrogel types, such as poly(acrylic acid) hydrogels, starch-based hydrogels, and superabsorbent polymers (SAPs) and superporous hydrogels (SPHs). The evolution of SPHs from conventional to advanced generations is detailed, highlighting their improved mechanical strength and elastic properties. The article concludes with a discussion on the innovative categories of hydrogel products, including the development of SPHs with enhanced properties for various industrial and environmental applications.This article provides a comprehensive review of hydrogels, focusing on their preparation, characterization, and applications. Hydrogels are polymeric materials with a hydrophilic structure that can hold large amounts of water in their three-dimensional networks. The review highlights the transition from natural to synthetic hydrogels due to their higher water absorption capacity, longer service life, and availability of raw chemical resources. It discusses the technological aspects of hydrogel production, including various synthesis methods such as bulk, solution, and suspension polymerization, as well as radiation-induced polymerization. The article also covers the classification of hydrogels based on their sources, polymeric composition, configuration, cross-linking, and electrical charge. Additionally, it explores the technical features and process design implications of hydrogel production, emphasizing the optimization of parameters for bead yield, smoothness, sphericity, and clarity. The review further delves into the preparation of specific hydrogel types, such as poly(acrylic acid) hydrogels, starch-based hydrogels, and superabsorbent polymers (SAPs) and superporous hydrogels (SPHs). The evolution of SPHs from conventional to advanced generations is detailed, highlighting their improved mechanical strength and elastic properties. The article concludes with a discussion on the innovative categories of hydrogel products, including the development of SPHs with enhanced properties for various industrial and environmental applications.