In previous versions of Event Viewer, you could filter the events in an event log. To create a filter, you specified a set of rules that were used to determine which events in the log would be visible and which would be hidden. You could, for instance, specify that only events with a level value of Error or Warning should be visible.
The ability to filter events is crucial. You need to focus your attention on only those events that apply to the issue you are investigating. The latest version of Event Viewer extends the filtering concept beyond a single event log. It enables you to create a set of rules which select events from the sources you specify and show only the events from those sources whose property values satisfy the rules.
Creating a filter that displays only the events you are interested in for a particular issue can be time-consuming. Custom Views provide a way for you to save that work. Once you have created a filter that displays just the records you are interested in, you can provide the filter with a name and save it to use later. That saved filter is a Custom View.