Explain why we use the letters V and v to represent the alleles for height

Alleles are the alternative form of gene. When we talk about the allele we have one capital letter that is V here and one is small letter that is v here. V represent the dominant allele and the v represent the recessive allele. V will show the dominant phenotype in the individual and it should have one copy of the allele, and the v will show recessive phenotype in the particular individual.