When a selection is made, the sample in the dialog box shows the results of the selections. Click the picture in the Preview box to see the transition again. You can make transition decisions for each slide in the sorter. The transition icon is added below the slide in Slide Sorter view to show that you've set a transition for this slide. A build slide is one in which each bullet point in the main text is revealed one at a time during a slide show.
Bullets can fly in from the top or bottom, checkerboard in, dissolve, and so on.
If you want the point to appear in a special way, select the visual effect you want in the Effect box. An icon will appear below the slide in the slide sorter if build effects are selected. It lets you hide a slide so that you can bypass it during an electronic slide show. If you hide it, an icon appears in the lower right corner of the slide that precedes it in your slide show. Then, if you decide you want to show the hidden slide, you can click that icon.