A domino is a small rectangular block bearing from one to six spots on each face, resembling those on a die. When a domino falls, it causes its neighbors to topple in a chain reaction. Dominoes can be used in games or to create mind-blowing structures. Creating a domino is a complex process that requires careful planning, a lot of energy, and the help of many tools and techniques. While most people think of dominoes when they hear the word, the term actually has several meanings. Domino, the game, is a form of abacus in which players compete to build rows of dominoes, the most recent being the last domino standing wins. The word may also refer to a hooded cloak worn with a mask during carnival season or at a masquerade, and, in its earlier sense, to a cape worn by a priest over a surplice. Hevesh, whose full name is Jennifer Hevesh, makes these amazing domino creations by following a version of the engineering-design process. First, she considers what she wants to accomplish and brainstorms ideas. She then designs a layout of the components she needs to achieve her goal, such as a large 3-D structure or a line of dominoes that will stand on end. She starts by making a prototype of each section of the design. After making sure the prototype works as planned, she begins putting the pieces together. She tests each section individually, and if necessary, she will tweak the design to make it work. She also films the whole process in slow motion, which allows her to make precise adjustments to ensure the dominoes fall in the right sequence and at the correct speed. As the dominoes begin to fall, their movement is similar to that of a neuron firing in your brain. The speed of a domino’s pulse is independent of its size, and the impulse travels at the same speed whether it’s from a giant statue or a single fingertip. The physics behind dominoes is very complex, but there are some basic principles that you can apply to any situation. One important principle is the law of conservation of energy. The law states that energy cannot be created or destroyed, but it can change from one form to another. For example, a domino’s upright position has potential energy, which is the stored energy it has because of its position. When the domino falls, much of this potential energy converts to kinetic energy, which gives the domino its push and causes it to knock over its neighbors. Physicist Stephen Morris explains that when a domino is stood up, it has potential energy because of its upright position. This energy is converted to kinetic energy when the domino falls, and then some of that kinetic energy is transmitted to each subsequent domino, providing the push needed to cause it to fall as well. This continues from domino to domino, creating a chain reaction that can continue until all of the dominoes have fallen.