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Ferrites constitue an important class of ferrimagnétique oxide materials which have been extensively investigated due to their interesting magnetic and electrical properties and wide range of technological applications. Among the different types of ferrites, hexagonal ferrites, particularly M-type magnetoplumbites such as BaFe₁₂O₁₉ and SrFe₁₂O₁₉, are of considerable importance because of their high magnetocrystalline anisotropy, large coercive force, moderate saturation magnetization and good chemical stability. In the present review, the crystal structures of spinel, garnet and hexagonal ferrites are discussed with emphasis on the S, R and T structural blocks and their influence on magnetic exchange interactions and anisotropy. Various synthesis techniques including conventional ceramic method, co-precipitation, sol–gel, hydrothermal, spray drying and glass crystallization methods are briefly described in relation to phase formation and microstructural development. The effect of cation substitution, particularly coupled substitutions such as Co²⁺–Ti⁴⁺, Zn²⁺–Ti⁴⁺ and Ni²⁺–Sn⁴⁺, on magnetic and dielectric properties has been highlighted. The importance of these materials in permanent magnets, microwave devices, electromagnetic wave absorption and other high-frequency applications is also presented.