This chapter provides a comprehensive overview of cell division and plant chromosomes, tracing the historical development of cell theory and its implications for understanding life. The concept of the cell originated with Robert Hooke in the seventeenth century when he observed box-shaped structures in cork, which he named “cells.” This discovery laid the groundwork for classical cell theory, formulated by Theodor Schwann and Matthias Schleiden in 1839, asserting that all organisms are composed of cells and that cells arise from preexisting cells, as emphasized by Rudolf Virchow’s contribution in 1858. Subsequent advancements in technology confirmed the cell as the fundamental unit of life, whether unicellular or multicellular, prokaryotic or eukaryotic. The chapter highlights crucial milestones, including Friedrich Miescher’s identification of DNA as the hereditary material in the nineteenth century and the groundbreaking work of Avery, MacLeod, and McCarty in 1944 that provided conclusive evidence of DNA’s genetic role. The introduction of terms such as “chromosome” by Heinrich Wilhelm Gottfried Waldeyer in 1888 and “genome” by Hans Winkler in 1920 established important connections in the study of genetics. Pioneers like Thomas Hunt Morgan contributed to our understanding of the relationship between genes and chromosomes, while Watson and Crick’s elucidation of DNA structure in 1953 bridged the gap between genetics and cellular biology. Along with the conceptual ideas, the chapter has given special emphasis on the classical and molecular structures of the chromosome, highlighting the integral roles of DNA and chromosomes in heredity, growth, and development. Plant cytogeneticists are acknowledged as key figures in genome research, underscoring the importance of cellular studies in advancing biological understanding.