In 3D printing, PETG stands for Polyethylene Terephthalate Glycol-modified. It is a type of thermoplastic polymer that is commonly used as a filament material for 3D printing. PETG offers a good balance of properties, including high strength, durability, transparency, and resistance to moisture and chemicals. It is known for its ease of printing, as it has a lower tendency to warp compared to other materials like ABS. PETG is often chosen for applications where impact resistance and flexibility are important, such as functional prototypes, mechanical parts, and household items.