I am using Linux Mint 19.1.
When I enter window tiling settings it is described as…
Enable Window Tiling and Snapping
In addition is has the settings….
Show snap on-screen display
Show tile heads-up-display
As well, when I hover the window near the edge is says…
Hold ctrl to enter snap mode
But I can not for the life of me figure out what is different between these two concepts. Holding ctrl to enter snap mode just turns the tiling boxes green.
Then only behaviour I see is windows being tiled to full, half and quarter sizes.
Best Answer
I was wondering the same thing and finally found the answer:
Visually, the two modes have nearly identical behavior, which is why it's confusing. As you noticed in both modes, the window you're dragging will take up the full, half, or quarter of the screen.
But when you use the modifier key (Ctrl by default) to switch to snapping mode, the window you snapped will be considered "part of the screen real estate." That means other windows you maximize will try to avoid the space occupied by the snapped window. If you tile rather than snap (i.e. the default if you don't use ctrl), maximized windows will simply cover it.
So the difference between the two modes is not really with the behavior of the current window you're snapping, but with the behavior of other windows that you maximize later on.
Source: http://segfault.linuxmint.com/2013/07/new-window-tiling-and-snapping-functionality/
Tested and confirmed on 19.1 Tessa