Products, also known as PLR, come in many different formats with the most popular being written products, such as articles and eBooks. You can also find software, video, audio and visual content with PLR. As for how people make money with PLR, the options are virtually endless.
So, If you are unfamiliar with PLR here is a little more information that may help:
https://en.wikipedia.org/wiki/Private_label_rights
