**Abstract**

The commercial or industrial applications of 3D printing or additive manufacturing are continuously increasing in diverse areas mainly in rapid prototyping. 3D printing has become part of a novel industrial growth area where simplification of assembly, waste minimization, and mass customization are important, such as aerospace, orthopedic and medical research, defense, and jewelry. There has been continuous growth or improvement in additive manufacturing, which includes the type of materials used, metamaterials, and advancements in the printers or the software. 3D printing has explored the areas where materials have been manufactured which are several times lightweight, high strength compared to traditional parts, and also resulted in a reduction in CO2 emissions. Biodegradability and sustainability are the major concern for any industry. The price of conventional thermoplastic filaments is one of the main sources of revenue and profitability for the industry. In addition to its relatively high price, some of the concerns in its wide use are the moisture resistance and VOC emissions, including iso-butanol and methyl-methacrylate (MMA) during 3D printing. These emissions cause voids in the structure which compromises the mechanical strength of the 3D-printed objects. Additives have been added with thermoplastics, such as diatoms and biodegradable materials, such as ceramics, biomaterials, graphene, carbon fibers, binders for metals, sand, and plaster to reduce the cost and VOC emissions. The cost of these additives is relatively less than the thermoplastic filaments. There has been tremendous innovative growth in the field of additive manufacturing, including solutions such as 3D-printed houses and titanium drones. The addition of additives opens the new potential applications in new arising technology, especially in robotics like behavior, mechanisms respond to user demands which are known as 4D printing where new dimension has been added to 3D printing. It is a process where a 3D-printed object transforms itself into another structure over the influence of external energy input, such as temperature, light, or other environmental stimuli. 4D printing is simply referred to as 3D printing transforming over time. 4D printing is an all-new emerging area in the field of additive manufacturing which has diverse applications in biomedical, defense, robotics, etc.

**Keywords:** 3D printing, biodegradability, thermoplastic filaments, additives, cost, biomaterials, 4D printing
