On most screens you can re-size or re-order the columns to suit your own preferences.
To allow these settings to remain as you left them they need to be saved or they will default back to the original when you navigate away from the screen you are on.
To do this you simply need to set the columns as you wish then click the "Refresh" button.
Once you do this the setting will be save and will be set as you left then next time you access the same screen.
Please note: there are some exceptions to this when the columns are required to be in a certain order for some functions.