Tammy Enz became a civil engineer because of her awe of the massive steel bridges that spanned the Mississippi River. She just had to figure out how they worked. Today, she still likes tinkering and figuring out how things work. When she isn't tinkering, she fixes up old houses and conducts experiments in her garden and kitchen. Most of all, she loves reading books about anything and everything and asking 'why?' Marcelo Baez is a professional illustrator and designer who has worked for international clients such as Microsoft, ESPN Magazine, Dallas Observer, The Weekend Australian Magazine just to name a few.