A Variant Call Format (VCF) file is a text file format used to represent genomic variations, such as single nucleotide polymorphisms (SNPs), insertions, deletions, and structural variants. Each variant is represented by a line that includes the chromosome, position, reference base(s), alternate base(s), and various annotation fields such as genotype, allele frequency, and quality scores. VCF files are crucial for storing and exchanging variant information and are widely used in research to track genetic differences across samples. They support metadata, genotype information, and complex annotations, making them the standard for variant representation in genomics.