A smart toilet is simply a bidet and toilet combination. In other words, you have an all in one system for using the bidet and toilet at the same time. It is smart because it is electric and has the ability to be customized by using controls such as a remote. Many of the features are automatic like autoflush when you stand up, dual flush which means it determines how much water to use based on how long you were sitting at the toilet and auto open and close lid. Plus, many have self cleaning features to keep the bidet sanitary automatically.