Some brick are available in a number of different sizes. Examples of typical brick sizes are; Standard, Modular, 4 x 8 Pavers,  Jumbo, Oversize, 2:1, 6 x 6 and 6 x 9.  Sometimes the size of the brick can limit the patterns that the brick can be installed in, and alternately some sizes offer more pattern options for brick installation. The PDFs above detail some brick pattern options.