In jazz and popular music, passages are often notated with slash noteheads that indicate no specific pitch. The notation can either include stems to indicate specifc rhythms, or the notation can be stemless and just indicate the beat.
Beat slashes have no stems and thus show no rhythm; just the beat itself. Depending on the content, this might indicate an improvised solo, and accompaniment pattern to be devised by the player, or a suggestion to continue in the style of previously notated passage. These slashes are often accompanied by chord symbols, which can also be added in the usual way.
To fill a range with slashes:
From the menu, select Tools→Fill with slashes
These slashes do not play, but the chord symbols do.
To notate a specific rhythm, use rhythmic slash notation. By default, these slashes do not play, but you can override that if you wish to enter specific notes or chord voicings you want to hear even though they will be turned into pitchless slashes in the notation.
If you wish to hear the playback of the notes you entered, select the applicable range of chords and check “Play” in the Properties: General panel.
To enter rhythms above the staff, use the same process, but enter the rhythm into voice 3. Use voice 4 for a rhythm below the staff.