A Tile is an image that represents a pinned app on Start. Live tiles on Start display information that are useful at a glance without opening an app.
The default for tile groups on Start is to have 3 columns of medium sized tiles, but Microsoft has heard feedback from many Insiders who wanted the ability to have a 4th column as well, so they could have two wide or large sized tiles side by side in a group. Starting with Windows 10 build 10547, a Show more tiles on Start setting has been added to be able to do this now. .
This tutorial will show you how to enable or disable the ability to change the Show more tiles on Start setting for all users in Windows 10.