Because texture and pattern make extensive use of repetition, the differences between the two can seem very slight at first. A pattern is more decorative and less tactile than a texture because it is more rigidly structured. Most patterns consist of a system and a module. A module is a unit that is repeated and the system determines how the modules are combined. One of the simplest patterns is the check repeat in which all the modules are evenly spaced both horizontally and vertically from each other. Notice how the amount of negative space affects the appearance of the pattern.