CHAPTER 1 APPS TO THE RESCUE An overloaded truck bounces down a city street It turns a corner too fast spilling half its load onto the road The driver speeds away leaving a sour-smelling mess A crowd gathers Emergency workers arrive What is that stinky stuff in the street Is it dangerous Apps can help emergency crews determine whether substances are dangerous 5
The emergency crew’s captain pulls out her smartphone and gives it a few taps Soon she identifies the material It’s poison The captain looks up how to clean the spill safely She’s using an app called Wireless Information System for Emergency Responders WISER WISER gives emergency workers the information they need to protect people It’s an app that saves lives You probably don’t have a mystery mess on your hands But apps can still come in handy Apps can help you find a basketball score listen to music or get answers to homework questions 6
Some apps help runners keep track of how far they have gone An app is a set of instructions that tells An app is a set of instructions that tells a computer or mobile device how to do something Without these instructions a smartphone would be a useless block of metal and plastic The set of instructions that make a computer or device work is called software It is written in code a language that computers understand 7
