Superimposition of two-dimensional pictures containing connected occasional matrix structures may deliver moiré designs. Superimposition of two associated layers including equal lines or bends may give rise line moireacute; designs. The development of one of the layers brings about a quicker development of the line moiré superimposition picture. Such optical increasing speed is known as moiré speedup (check for the recipes of optical speedup for bended examples). While superimposing two indistinguishable layers containing haphazardly divided equal lines, at a little edge or with a little scaling contrast arbitrary line moiré patterns,in particular line Glass designs (after Leon Glass, 1969) show up. Likewise, while superimposing two indistinguishable layers of haphazardly dispersed dabs at a little edge or with a little scaling contrast irregular speck Glass designs, to be specific arbitrary dab moiré shows up. At the point when one of the layers inserts complex shapes, for example, groupings of images framing a book, and another layer contains equal lines or bends, the superimposition picture may offer ascent to amplified shapes, called shape moireacute designs.