No matter which tool you've configured to perform file comparisons, you invoke the tool in the same way, as described below. AccuRev's Diff tool opens in a separate tab within the AccuRev GUI window; any other tool opens in its own window.
In a File Browser, each file's context menu includes a Diff Against... item. There are several choices, each of which compares your version (i.e. the file in your workspace) with a version stored in the depot:
In a Stream Browser display, view the elements in a stream's default group by clicking the

control below the stream. An element's context menu includes the
Diff Against... items described above.
In a Version Browser or Stream Version Browser display for a text-file element, you can compare any two versions: right-click any version, select
Diff Against Other Version from the context menu, then left-click any other version.
In a History Browser display for a text-file element, you can compare the versions created in any two transactions. Right-click a transaction in the Summary (upper) pane, select
Diff Against Other Version from the context menu, then left-click another transaction in the Summary pane. Similarly, the
Diff Against File in the Workspace command enables you to compare the version created in a particular transaction with the file currently in your workspace. (That file might contain changes that you haven't yet preserved with
Keep.)