Differences between .ContextMenu and .ContextMenuStrip

Question

What are the differences between .ContextMenu and .ContextMenuStrip in Windows Forms?

I already know what a ContextMenu is, but ho

Answer 1

According to the MSDN, the ContextMenuStrip replaces the ContextMenu class:

Although ContextMenuStrip replaces and adds functionality to the ContextMenu control of previous versions, ContextMenu is retained for both backward compatibility and future use if you choose.

Source: MSDN - ContextMenu

Edit: why the -1?