If you are using images (jpgs, pngs, gifs, svgs, etc.), this is the place to put them.
If you don't plan using images, feel free to delete this folder and the tasks.images config in gulpfile.js/config.json.
gulpfile.js/tasks/images
The image task will copy them over to the destination specified in config.json, and run lossless optimizations and compression on them. File names will be reved in production builds (if enabled).