By default, there are 6 product types in Magento 2: Simple, Configurable, Virtual, Downloadable, Grouped & Bundle Products. They are the same as in Magento 1. If you are using Magento 1, I guess you are immensely familiar with these types of product. However, if you are still curious and want to understand more about them, here you go. This blog will give you a detailed description for each product type.