What are the best materials to use for building sturdy garage shelves, particularly focusing on the durability and strength of wood?

When building sturdy garage shelves, the best materials to use for durability and strength are hardwoods such as oak, maple, or birch. These woods are strong and can withstand heavy loads without warping or bending. Additionally, using plywood or MDF (medium-density fiberboard) can also provide good strength and stability for garage shelves.