One of the research and development disciplines with the fastest global growth is nanotechnology. In the areas of energy, electronics, data storage, food, and healthcare, it brings about revolutionary technologies and drives revolutions. Magnetic nanoparticles (MNPs) show different properties from their bulk counterparts due to their large ratio of surface to volume, increasing their reactivity. Different methods are utilized for their synthesis, these methods include physical, chemical, and biological synthetic methods. The obtained MNPs are then characterized using variable characterization techniques. The fusion of nanotechnology and medical applications, or so-called biomedical applications of nanotechnology, is a field for development, allowing for their biological applications in many fields as drug delivery systems, gene therapy, use as antibacterial drugs, and utilization in tissue engineering. Various types of MNPs whether mono component or coated ones have been synthesized serving such mentioned purposes, but a few reviews have dealt with such topic The growing interest in MNPs has inspired us to design this review focusing on the composition, synthesis, characterization, and recent applications of MNPs.