The HapMap Web site at http://www.hapmap.org serves as the primary portal for genotype data from the International Haplotype Map Project. In its first phase, over 1.1 million SNPs were genotyped in 270 individuals from four global populations. The site provides researchers with tools for analyzing and downloading data, including retrieving genotype and frequency data, selecting tag-SNPs for association studies, viewing haplotypes graphically, and examining LD patterns. The site is organized into three main sections: Home, About the Project, and Data. The Data section offers bulk downloads, interactive data browsing, and analysis tools. The site supports multiple languages and has been widely used, with over 500,000 downloads and 30,000 monthly page requests. Future developments include integrating with other genome browsers, enhancing data mining capabilities, and providing more sophisticated visualization tools for genetic association studies.The HapMap Web site at http://www.hapmap.org serves as the primary portal for genotype data from the International Haplotype Map Project. In its first phase, over 1.1 million SNPs were genotyped in 270 individuals from four global populations. The site provides researchers with tools for analyzing and downloading data, including retrieving genotype and frequency data, selecting tag-SNPs for association studies, viewing haplotypes graphically, and examining LD patterns. The site is organized into three main sections: Home, About the Project, and Data. The Data section offers bulk downloads, interactive data browsing, and analysis tools. The site supports multiple languages and has been widely used, with over 500,000 downloads and 30,000 monthly page requests. Future developments include integrating with other genome browsers, enhancing data mining capabilities, and providing more sophisticated visualization tools for genetic association studies.