In the transportation sector, weight-saving strategies emphasize greenhouse gas reductions by improving fuel efficiency. Furthermore, it is a fact that consumers appreciate less-consuming vehicles. Lighter battery electric vehicles (BEV) mean higher travel distance covered with the same battery charge. Still, the fuel range of BEV is today not a secondary issue for choosing an e-vehicle as a unique family vehicle. Weight-saving strategies are also a priority for hydrogen gas-fuelled vehicles. Until hydrogen fuel for the transport sector is not produced at affordable costs in fully renewable pathways, increased fuel efficiency is critical for the product appeal. Magnesium is an environmentally compatible and biodegradable material with a similar density to structural plastics. On the contrary, plastics are responsible for nonbiodegradable microplastics in deep-marine environments when not recycled or correctly treated at their end of life. Due to the costly usage of lightweight materials, priority is given to activities to reduce costs by developing new materials and increasing the affordability of manufacturing costs. In this chapter, magnesium is presented from much perspective point of view: we will base it on comprehension of the past, considering the present, but with some ambition to propel hearts over today’s obstacles.