Zaks are a building toy

Toy

A toy is any object that can be used for play. Toys are associated commonly with children and pets. Playing with toys is often thought to be an enjoyable means of training the young for life in human society. Different materials are used to make toys enjoyable and cuddly to both young and old...

 originally produced by the company Ohio Art. They consist primarily of equilateral

Equilateral

In geometry, an equilateral polygon is a polygon which has all sides of the same length.For instance, an equilateral triangle is a triangle of equal edge lengths...

 triangles and squares

Square (geometry)

In geometry, a square is a regular quadrilateral. This means that it has four equal sides and four equal angles...

 with toothed, hinged, and interlocking edges. The basic triangle and square shapes are further modified by having a number of different face styles, including holes or extended sockets that allow them to connect face-to-face. The toys can be attached to one another to build three-dimensional creations, with the edges either remaining rigid or being allowed to swivel. It is quite easy to create Platonic solids using Zaks, and the toys are useful to demonstrate how simple planes like triangles and squares can be used to create complex polyhedra. Since the pieces primarily connect with hinges, building a rigid structure takes some work, either by clever geometry or socketing together smaller polyhedra.

Zaks (Ziegler's Animated Konstruction System), was invented by Calgary designer Jim Ziegler. After building a virtually complete product that required $75,000 of his own money, Ziegler approached the product manager at Irwin Toy Limited, Dave Irwin, with his concept. Dave called on his brother George Irwin, and the two Irwins decided to give the toy a shot. Irwin Toy Limited was launching an important new profit center during the mid-1980s: product development, and in 1985 Irwin developed and started marketing Zaks. Zaks was a hit during its first Christmas season, and Irwin was able to quickly sell licenses to companies in the United States and Australia.

Zaks were manufactured through the late 1980s and early 1990s, but production is now discontinued. They found some success, and can still be found for sale used.