The Zedonk grids are very dynamic, allowing you to add and remove columns, as well as reposition them where you want them to be and resize them individually.
However you might end up with columns not displaying the whole data or not fitting your screen correctly.
Autosize Columns
This resize your columns to show the full data for all the fields currently displayed on your screen.
This could result in the grid being wider than your screen and you will be able to scroll right/left to see all data.
Fit To Screen
This will fit your columns to the size of your browser window.
This could result in some data not being displayed in full, in case you have many columns fit in a narrow window.