Charm packs contain 42 fabrics from an individual collection cut down to a 5 inch square.  Perfect for a quick project or just to collect.

 Layer Cakes are collections of 10" x 10" squares of fabric. Made originally by Moda Fabrics, they are similar to a charm pack. Layer Cakes typically include 42 pieces of fabric, though the number may vary.

Moda's Mini Charms are collections of 2.5" x 2.5" squares.  These are great for small projects or to just collect!!