Worksheet.Name (Excel)

Returns or sets a String value that represents the object name.

' This macro sets today's date as the name for the current sheet 
Sub NameWorksheetByDate() 
    'Changing the sheet name to today's date
    ActiveSheet.Name = Format(Now(), "dd-mm-yyyy")

    'Changing the sheet name to a value from a cell
    ActiveSheet.Name = ActiveSheet.Range("A1").value
End Sub