So I have this code which uses the dictionary object to find unique values in column F. Some of the code was pieced together from internet examples and my current knowledge. I understand how it works except for this line. 
DXNRY(CStr(Range("F" & z))) = 1
. What does the "= 1" do? Does it matter what that is set to? Any information is appreciated. Below is the full code:

Function unique()

Dim a As Long, z As Long
Dim v As Variant
Dim DXNRY As Object

Set DXNRY = CreateObject("Scripting.Dictionary")

'-------------------------------------------------------------------
'Makes sure the Formatting Page is activated.
Worksheets("Formatting").Activate
'Counts and stores data length
a = Range("A" & Rows.Count).End(xlUp).Row
'-------------------------------------------------------------------

For z = 1 To a
    DXNRY(CStr(Range("F" & z))) = 1
Next z

For Each v In DXNRY.Keys
    Debug.Print v
Next v

DXNRY.RemoveAll
Set DXNRY = Nothing

End Function