This page shows a list of all files and folders that have labels assigned to them. You can label files and folders using this interface; another way to do it is to use the Set Label command in the Properties drop-down on the default Operations toolbar. Note that if the label is stored in the file system (depending on the options on the Options page), they will not appear in this list.
The New dropdown lets you assign labels in a few ways:
By default filter and wildcard labels assignments will "stack" on top of each other. One label could change the color of an icon, and another could change the icon itself. You can use the Stop on match option on both wildcard labels and label filters to prevent this from happening.
Note that filter and wildcard label assignments can be rearranged to control their priority.
When creating a wildcard label, the following options are available: