Keep in mind that when using Align To Artboard, any overlapping areas between adjacent objects will be merged together into one big blob; this can result in unexpected results if your artwork contains complex shapes or textures. Conversely, when using Alind To Selection, overlapping areas will remain separate; however, this can lead to more complicated alignment problems if your artwork contains lots of small details. Finally, it's worth noting that both options allow you to fine-tune alignment settings by dragging individual object corners directly onto corresponding grid points on either side of the artboard border (or selection boundary).