Introduction

Time changes things. When I was a child, we only had black and white television that went off the air at 10 p.m. Then, later came color television that stayed on all night and had remote control switches. Later, we had transistor radios we could carry in our pocket. Next, we had early computers where we programmed them with computer cards. Quickly, the computers became more sophisticated and portable. Today, we have phones that work like computers and connect us through voice, visual picture, and text with people next door and around the world. We have transportation systems that allow us to travel to far away continents in a matter of hours. And rockets that take people to the moon and into outer space. Indeed, time changes things.