Difference between boiler plat images and image items

What is the difference between boiler plat images and image items? 
Boiler plate Images are static images (Either vector or bit map) that you import from the file system or database to use a graphical elements in your form, such as company logos and maps. Image items are special types of interface controls that store and display either vector or bitmap images. Like other items that store values, image items can be either base table items(items that relate directly to database columns) or control items. The definition of an image item is stored as part of the form module FMB and FMX files, but no image file is actually associated with an image item until the item is populate at run time.

What are the triggers available in the reports?
Before report, Before form, After form , Between page, After report.

Why is a Where clause faster than a group filter or a format trigger? 
Because, in a where clause the condition is applied during data retrievalthan after retrieving the data.