Nanomaterials: an introductionThe size regime at the nanoscale (1-100 nm) is observed as the intermediate size between macroscopic crystals (bulk materials) and atoms or molecules . Due to their fixed energy levels and molecular homogeneity, atoms and small molecules have found many applications in areas such as remote sensing1, trace detection2, understanding atmospheric chemistry and have made the subject of investigations in mass spectrometry3 and gas phase laser spectroscopy4. On the other hand, by varying the composition, configuration and purity of macroscopic crystals, materials with new electronic, magnetic, optical and mechanical properties have been created, very different from atoms and molecules of the same composition. The scope of this research focuses on a size scale in which at least one of the dimensions is less than 100 nm. The high surface-to-volume ratio observed in nanomaterials often gives them unique and exciting properties, very different from mass and atomic size scales, and this has been the subject of intense scientific research around the world. Nanomaterial Fabrication: Extensive research over the past decade has led to new manufacturing techniques for the synthesis of nanomaterials with different physical and chemical properties. The two main synthesis routes used are the “top down” approach and the “bottom up” approach. Lithography is a highly developed top-down technique that is used to etch nanoscale features into silicon and other semiconductors often used in the electronics industry. On the other hand, DNA and RNA are examples of natural biological systems built using a bottom-up approach starting from amino and nucleic acids. This biological assembly process is known as self-assembly where the complex medium of the paper......the individual atomic moments observed in ferromagnets, antiferromagnets, and ferrimagnets are typically aligned along a preferred or easy axis in the absence of an external magnetic field. In order to reverse their magnetic moments, the magnetocrystalline anisotropy (EA) which scales linearly with the core volume must be overcome. Below the critical size, the (EA) is comparable to the ambient thermal energy (kBT), thereby causing the magnetic moment of the single-domain magnetic NP to fluctuate, and this property is known as superparamagnetism. Magnetic NPs have many applications in the areas of magnetic recording (if superparamagnetism can be overcome), medical resonance imaging, drug delivery (when functionalized with ligands and proteins organic), hyperthermia and cancer treatment, core-shell nanostructures of magnetic semiconductors and future applications in spintronics.13.