Observer Apex : Apex Filters : Apex filters
Apex filters
Use filters on dashboards or widgets to isolate just the object of interest for you, such as a specific application, IP or MAC address, or telephone number in a VoIP conversation.
 
Conventions used in this document:
Filters typed by the user will be shown in Bold Courier
Filter names are written in red.
Angled brackets < and > surround required arguments.
Square brackets [ and ] surround optional arguments.
Choices are separated by a vertical bar |.
Single quotes ' ' are required for any parameter or text containing a space.
Filter names are case sensitive (for instance, fixRequest or networkType).
Parameters are case-insensitive.