Can anyone please please explain to me what 'rOld', and 'Dim i' means???


Private Sub Worksheet_SelectionChange(ByVal Target As Excel.Range)
Const cnNUMCOLS As Long = 256
Const cnHIGHLIGHTCOLOR As Long = 36 'default lt. yellow
Static rOld As Range
Static nColorIndices(1 To cnNUMCOLS) As Long
Dim i As Long
If Not rOld Is Nothing Then 'Restore color indices
With rOld.Cells
If .Row = ActiveCell.Row Then Exit Sub 'same row, don't restore
For i = 1 To cnNUMCOLS
.Item(i).Interior.ColorIndex = nColorIndices(i)
Next i
End With
End If
If ActiveCell.Row <> 1 Then 'don't colour if row 1
Set rOld = Cells(ActiveCell.Row, 1).Resize(1, cnNUMCOLS)
With rOld
For i = 1 To cnNUMCOLS
nColorIndices(i) = .Item(i).Interior.ColorIndex
Next i
.Interior.ColorIndex = cnHIGHLIGHTCOLOR
End With
End If
End Sub
Thank you so much!!