Nanotechnology, a field rooted in the manipulation of matter at the atomic and molecular levels, has significantly evolved since its conceptual inception, offering unprecedented advancements across various disciplines. This chapter provides an introduction to nanotechnology and nanomaterials, tracing their historical development from early theoretical frameworks to contemporary applications. It explores the basic concepts and definitions essential to understanding nanotechnology, including the scale of nanomaterials, their unique properties, and the techniques used for their synthesis and characterization. Special attention is given to the scope and applications of nanotechnology in agriculture, where it has emerged as a transformative tool. Nanomaterials are employed in diverse agricultural practices, from enhancing crop yield and soil health to improving pest management and food safety. The paper also discusses the integration of nanotechnology in smart delivery systems for fertilizers and pesticides, which allows for targeted and efficient resource use, thereby reducing environmental impact. Additionally, the role of nanomaterials in post-harvest management, such as food preservation and packaging, is highlighted. Through a review of current research and case studies, the paper underscores the potential of nanotechnology to address critical challenges in agriculture, including food security, sustainable farming practices, and environmental conservation. Therefore, this provides a comprehensive overview of the historical background, fundamental concepts, and wide-ranging applications of nanotechnology and nanomaterials, with a focus on their significant contributions to modern agricultural practices.