Granitic rocks can originate from a wide range of sources, from pure mantle to pure crust, and their tectonic settings significantly influence their characteristics. Ocean ridge granites typically have depleted mantle sources, while volcanic arc granites often have modified depleted mantle sources with contributions from subducted oceanic crust and sediment. Intraplate granites usually show evidence of enriched mantle sources, along with rare crustal melts. Syn-collision granites are characterized by pure crustal sources or mantle sources containing large subducted crustal components, while post-collision granites carry signs of enriched lithospheric mantle sources and rare crustal melts. The interaction between mantle-derived magma and the crust is influenced by the thickness, temperature, and composition of the crust, as well as the residence time and temperature of the magma, all of which are linked to tectonic settings. The geochemical fingerprinting of granites, combined with geological considerations, helps assign granites to their most probable intrusion setting. The paper defines granites broadly as coarse-grained igneous rocks containing more than five percent quartz, sources as the mantle or crustal protoliths contributing to granitic magma, and settings as the global tectonic environment where the parent magma is generated. The sources of granitic magma can be either pure mantle or pure crust, or a mixed source combining both. The variability in granite composition results from differences in the composition of the end-member sources, the degree of melting, and the interaction between mantle and crust. Mantle source variables include rock type and depth, with igneous and sedimentary protoliths being the primary sources. The degree of melting is influenced by the presence of free fluid, mineralogy, temperature, and pressure. Tectonic settings such as mid-ocean ridges, volcanic arcs, within-plate settings, and collision settings each have distinct characteristics and associated granites. Mid-ocean ridges typically have depleted asthenospheric mantle sources, while volcanic arcs form by melting of mantle asthenosphere modified by subduction components. Within-plate settings, such as ocean islands and continental intraplate settings, are influenced by mantle plume activity or passive rifting. Collision settings, including syn-collision and post-collision, involve crustal thickening or rapid uplift after collision, leading to extensive magma-crust interaction. Geochemical diagrams, such as the Rb-(Y+Nb) diagram, help discriminate between different tectonic settings of granites. Ocean ridge granites plot at the bottom of the diagram due to their depleted mantle sources and lack of crustal interaction. Within-plate granites occupy the upper-right field, reflecting enriched mantle sources and anhydrous crystallization. Volcanic arc granites and syn-collision granites have varying compositions, with volcanic arc granites influenced by subduction components and syn-collision granites by melts and fluids from subducted or underthrust continental crust. Post-collision granites are the most challengingGranitic rocks can originate from a wide range of sources, from pure mantle to pure crust, and their tectonic settings significantly influence their characteristics. Ocean ridge granites typically have depleted mantle sources, while volcanic arc granites often have modified depleted mantle sources with contributions from subducted oceanic crust and sediment. Intraplate granites usually show evidence of enriched mantle sources, along with rare crustal melts. Syn-collision granites are characterized by pure crustal sources or mantle sources containing large subducted crustal components, while post-collision granites carry signs of enriched lithospheric mantle sources and rare crustal melts. The interaction between mantle-derived magma and the crust is influenced by the thickness, temperature, and composition of the crust, as well as the residence time and temperature of the magma, all of which are linked to tectonic settings. The geochemical fingerprinting of granites, combined with geological considerations, helps assign granites to their most probable intrusion setting. The paper defines granites broadly as coarse-grained igneous rocks containing more than five percent quartz, sources as the mantle or crustal protoliths contributing to granitic magma, and settings as the global tectonic environment where the parent magma is generated. The sources of granitic magma can be either pure mantle or pure crust, or a mixed source combining both. The variability in granite composition results from differences in the composition of the end-member sources, the degree of melting, and the interaction between mantle and crust. Mantle source variables include rock type and depth, with igneous and sedimentary protoliths being the primary sources. The degree of melting is influenced by the presence of free fluid, mineralogy, temperature, and pressure. Tectonic settings such as mid-ocean ridges, volcanic arcs, within-plate settings, and collision settings each have distinct characteristics and associated granites. Mid-ocean ridges typically have depleted asthenospheric mantle sources, while volcanic arcs form by melting of mantle asthenosphere modified by subduction components. Within-plate settings, such as ocean islands and continental intraplate settings, are influenced by mantle plume activity or passive rifting. Collision settings, including syn-collision and post-collision, involve crustal thickening or rapid uplift after collision, leading to extensive magma-crust interaction. Geochemical diagrams, such as the Rb-(Y+Nb) diagram, help discriminate between different tectonic settings of granites. Ocean ridge granites plot at the bottom of the diagram due to their depleted mantle sources and lack of crustal interaction. Within-plate granites occupy the upper-right field, reflecting enriched mantle sources and anhydrous crystallization. Volcanic arc granites and syn-collision granites have varying compositions, with volcanic arc granites influenced by subduction components and syn-collision granites by melts and fluids from subducted or underthrust continental crust. Post-collision granites are the most challenging