The Labels system lets you assign your own labels to files and folders. A label has a name, and can define colors and font styles that modify the appearance of labeled files. Labels can also be used to override the default icon image for a file or folder. By default Opus defines five labels - Blue, Green, Orange, Purple and Red. You can use these labels (what you interpret them to mean is up to you) or define your own. For example, you could define a label called Important that displays files in red italics.
Labels are defined through the Favorites and Recent / File and Folder Labels page in Preferences. On this page you can create and modify your own labels, and you can also view a list of all files and folders that have had labels applied to them. Labels can be applied to specific files and folders, and can also be applied using wildcard patterns. For example, you could cause all Word documents to be labeled Green by creating a wildcard label assignment for *.doc files. Labels can also use filters to perform tests based on attributes other than file name or path.
The Properties drop-down menu on the default toolbar displays a list of your defined labels, and lets you apply them automatically to selected files and folders.
To label a file, select it, and then choose the appropriate label from this drop-down. Depending on the label definition, the file will change color instantly to match the assigned label. One thing to be aware of is that (except for wildcard labels), labels store the full filename and path of the labeled file. That means that if you move a labeled file, the label will not go with it. You can view a list of all your labeled files from the File and Folder Labels page in Preferences, and use the controls there to clean up the labeled file list.