In the Explorer model, if there are objects underneath a node (for example, a directory), there will be a + sign next to the object, enabling you to click it and drop down the hierarchy to view them. Typically, an Explorer is programmed where you read the disk only when requested, but to display the + sign, Translator has to read the contents anyway to find out if there are any objects contained underneath - which is the Look Ahead. You can uncheck these options to speed up the reading of objects - then every node will have a + sign, until you look underneath the node - if there are no objects, the + sign will be removed.
