Popular with both weekend do it yourself types and professional carpenters, the zig-zag rule is a useful addition to any toolbox. Constructed with one foot sections that fold into a compact design, the zig-zag rule works well with measurement tasks that do not lend themselves easily to the use of tape measures or retractable rulers. Sometimes referred to as a folding ruler, the zig-zag rule was developed in the late 19th century, and quickly became an essential tool around the house as well as at building sites.

The first versions of the zig-zag rule were constructed from wood, with simple metal connections between each section of the rule. Part of the charm of the simple construction allowed folding rulers to be extended a section at a time, with each section snapping into place to form a level linear projection. Zig-zag rules offered an improvement over standard yardsticks, since the zig-zag rule would provide a linear measurement of up to six feet.

During the 20th century, enhancements were made to the zig-zag rule. Lightweight models constructed of aluminum began to compete with the traditional wood models. By the middle of the century, the linear measurement capability of the zig-zag rule was improved with the addition of metric measurements. This simple innovation helped to expand the consumer market for the zig-zag rule, while still retaining the core audience.

In spite of the proliferation of more high-tech measuring solutions, the zig-zag rule continues to be a popular option for many types of construction projects. Both the traditional wood ruler and the aluminum versions of the zig-zag rule are still available for purchase at hardware stores and home improvement outlets. Fitting easily into any toolbox, the zig-zag rule requires no batteries or power source, is portable, and will not break if accidentally dropped on concrete. For all these reasons, chances are the zig-zag rule will continue to be a popular tool for many years to come.