Let’s say you’ve just shot a wedding, and in the Grid view you now see thumbnails of literally hundreds of photos. Finding the "keepers" seems pretty daunting, but you can reduce clutter and work more efficiently by grouping (stacking) similar photos. For example, if you have 12 shots of a particular pose, stack them together. That way, just one photo thumbnail of that pose will represent all 12 shots of that pose. You can collapse and expand these photo stacks in just one click, plus Photoshop Lightroom can even do your stacking automatically, based on time intervals.