This chapter provides a detailed overview of soil organic matter (SOM) and soil organic carbon (SOC), emphasizing their fundamental roles in soil fertility, nutrient cycling, and climate change mitigation. It discusses SOM as a vital reservoir of nutrients and energy for soil microorganisms, highlighting its impact on soil’s physical, chemical, and biological health. The chapter also explores various carbon fractions, including particulate organic carbon (POC), dissolved organic carbon (DOC), microbial biomass carbon (MBC), mineral-associated organic carbon (MOC), and their significance in carbon farming and nutrient dynamics. Additionally, it highlights the importance of carbon sequestration in mitigating greenhouse gases and preserving the global carbon balance, referencing regenerative agriculture and the CSIFRA project by ICRISAT. The chapter concludes with laboratory safety guidelines for chemical handling, waste management, and equipment maintenance, ensuring safe and effective analytical practices. Collectively, these elements provide a solid methodological and conceptual foundation for measuring soil carbon, understanding its ecological roles, and promoting sustainable soil management in the context of climate change.