Establishing a historical baseline of data is critical to monitoring systems, and Salt has been using returners to do this since the beginning. You can also use monitoring states and beacons to collect data and perform actions based on it.
Salt has a very powerful set of tools to monitor systems in order to establish a baseline of information and raise alerts when something goes awry.
Thorium can be used to collect aggregate data and perform operations based on statistical analysis of it.
In the next chapter, we'll take a look at some of the best and worst practices in Salt.