Fused Deposition Modeling (FDM), one of the most widely used additive manufacturing technologies, has gained significant attention due to its cost-effectiveness, flexibility in material selection, and ease of use. This method involves the layer-by-layer deposition of thermoplastic filaments melted through a nozzle to fabricate three-dimensional objects based on digital models. FDM is extensively utilized in both industrial and academic settings for prototyping and producing functional components across various sectors, including automotive, aerospace, biomedical engineering, and education. The process enables the creation of complex geometries that are difficult to achieve with traditional manufacturing methods, while also minimizing material waste. However, despite its advantages such as rapid prototyping, simplicity, and compatibility with a wide range of materials—including PLA, ABS, PETG, and fiber-reinforced composites—FDM has inherent limitations. These include anisotropic mechanical properties, surface roughness, limited dimensional accuracy, and potential printing errors such as warping, layer shifting, and nozzle clogging. Several process parameters, such as layer height, nozzle temperature, infill percentage, and build platform temperature, significantly influence the final product's quality and mechanical performance. Optimization of these parameters is crucial for improving part strength, dimensional accuracy, and surface finish. Recent advancements aim to enhance FDM’s capabilities through innovations like continuous fiber reinforcement, 4D printing, and the use of recycled materials. This review highlights the theoretical background, working principles, materials, parameters, challenges, and application areas of FDM technology. It also emphasizes the importance of ongoing research in material development, process optimization, and system design to expand FDM’s applicability beyond prototyping into serial production and high-performance industries.