This is a ghost mannequin tutorial. It’s another name is invisible mannequin or neck joint service. The flat images of eCommerce product like shirts, sweater, hoodie sweater, T-shirts etc. aren’t looked real. That is why, the product photographers, during taking these images use a doll or mannequin to make a 3D shape which gives a realistic view.
Again, the images with the doll or mannequin cannot be used directly. So, these objects need to be removed from product image to make usable in the business purposes.