|Definition:|| Free text description of what data are collected and how they are organized.
|Examples:||"IRIS DMC provides time series data from the 1960’s until present. Data from more than 3500 stations comes to us in real time and can be distributed in real time. While most data is from the earth, IRIS has the Apollo Lunar Seismic Data and will have data from the Martian seismic experiment t when it becomes avaialble. All data, both historical and current are seamlessly available through open web services. Mostly time series data from roughly 30 different types of sensors including ground motion, infrasound, barographic, weather measurements, etc."|