I have a spreadsheet that was sent to me that contains buttons in the top
cell of each column that are used to sort with. Each button works
independently, but the sort is cumulative.

I have no idea how these buttons were created, but they are very handy. Now
I am creating a new spreadsheet, but have not been able to duplicate these
buttons. The help files are not really helpful in this matter.

Any ideas what these are called and how to create them?