Human genetics studies the inheritance and variation of genes in individuals and populations. Research methods such as genealogical analysis, twin studies, and population statistical approaches provide complementary insights into genetic architecture, heritability, and the distribution of alleles. Genealogical methods help trace inheritance patterns within families, while twin studies estimate the relative contributions of genetics and environment to complex traits. Population statistical methods, including the analysis of allele and genotype frequencies and the Hardy–Weinberg equilibrium, allow researchers to assess genetic variation and evolutionary forces at the population level. This article reviews these methods, their applications in epidemiology and disease studies, and discusses their advantages, limitations, and methodological challenges. The integration of these approaches improves our understanding of human genetic diversity and informs public health, disease prevention, and personalized medicine.