The Metadata Panel provides information about the data. It is a tree view that contains a number of nodes of information.
The Metadata node is metadata provided by the data source. In general, Autoplot doesn't understand the metadata and simply provides it for reference by the user. However, if the data source also identifies a "metadata model," this is indicated in parenthesis and Autoplot will use the metadata to get axis labels and ranges.
The Statistics node provides basic statistics about the data. For example it shows the mean and standard deviation, and the number of valid points. Cadence indicates the typical spacing between points and is used to insert breaks in time series.
The Dataset node allows some inspection of the dataset itsself. The size of the dataset, its named dimensions, and their size are identified. Metadata for plotting found within the dataset is available as well. You can look at the digital data (though only the first twenty or so points) as well.
this page in the wiki