Possessing a single set of chromosomes, haploid organisms have long intrigued scientists due to their unique genetic characteristics and evolutionary significance. Historically, the field began with pioneering experiments that led to the generation of haploid plants, offering a unique platform for studying plant genetics. The advent of in vitro culture techniques in the mid-twentieth century marked a significant milestone, enabling efficient production of haploid plants from various tissues. For haploid generation two different approaches can be used: in vitro and in vivo (in seed). Through the in vitro development of gametophytes (microspores and megaspores) or the floral tissues or organs that surround them (anthers, ovaries, or ovules), in vivo techniques include wide crossing, pollen irradiation and in some cases the use of genetically defective haploid inducer lines. Moreover, the application of molecular markers and genomics tools has expedited the identification and selection of haploid plants carrying desirable traits. Gene editing technology has further facilitated the development of haploid plants with targeted genetic modifications revolutionizing the field of functional genomics and trait improvement. By synthesizing historical perspectives with contemporary insights, this chapter provides a comprehensive overview of the enduring significance of haploidy in genetics, genomics, and biotechnology highlighting the remarkable progress in haploidy.