PLINK is one of the most core toolkits in the field of genome-wide association analysis (GWAS). It offers a complete functional chain ranging from data management (format conversion, sample/snp filtering), quality control (missing rate, MAF filtering, HWE test) to association analysis (chi-square test, logistic regression, linear regression) and population genetics analysis (IBD estimation, kinship matrix calculation). PLINK supports multiple input formats (BED/PED/VCF/Oxford, etc.), and is the standard tool for GWAS data preprocessing and basic analysis.