Preferences are different GUI settings, accessible via "Settings->Preferences". Below is the description of most important ones.

Skin

Switches between light/dark skins

Colors

Highlight colors for current row, selected rows and asset background color

Navigation

Provides the options to disable navigation arrows, right-click navigation and to ignore navigation move if no entity was selected. More details about navigation can be found here

Popup row editor

Popup row editor is a popup window for editing row's values. It can be opened via "M" menu or via special additional column with "f" button. There is also an option to show row editor window on row adding.

Vertical tab

Defines in which direction cursor moves when Tab/Shift+Tab is pressed

Save popup window position

Many field values are edited via popup windows. By default, this window position depends on current mouse position, but you can make this popup window position persistent across multiple sessions

Other settings

There are many other preferences are available. Hover your mouse over the label to learn which effect the specific configuration setting has