To hide from the UI, use Format > Sheet > Hide
To hide programatically, use the Visible
property of the Worksheet
object. If you do it programatically, you can set the sheet as “very hidden”, which means it cannot be unhidden through the UI.
ActiveWorkbook.Sheets("Name").Visible = xlSheetVeryHidden
' or xlSheetHidden or xlSheetVisible
You can also set the Visible property through the properties pane for the worksheet in the VBA IDE (ALT+F11).