Sheets(1).Activate and Sheets(1).Select looks like doing the exactly same thing.
Although, the code Sheets(1).Select fails when the worksheet is invisible.
As for Activate method, it works.
The workbook as the parent object is activeted.
is a method for activating objects.
is a method for selecting objects.
You can select plural worksheets but cannot activate both worksheet.
Only you can do is activate a worksheet.
Place the following in a worksheet module.
ActiveWorkbook.Sheets(Array(1, 2, 3)).Select
'does not work
ActiveWorkbook.Sheets(Array(1, 2, 3)).Activate