The main components of a nucleotide are three essential parts: a nitrogenous base, a sugar, and a phosphate group. The nitrogenous base can be one of five types: adenine, thymine, cytosine, guanine, or uracil (in RNA). The sugar molecule can either be ribose (in RNA) or deoxyribose (in DNA). The phosphate group links the nucleotides together, forming the backbone of the nucleic acid structure. Nucleotides are the building blocks of both DNA and RNA, playing a vital role in genetic information storage and transmission during cell division and protein synthesis.