Not so long ago, maths problems had to be solved with pencil and paper, post delivered by postman, and files were stored in paper folders and metal cabinets. But three women, Betty Snyder, Jean Jennings, and Kay McNulty knew there could be a better way. During World War II, people hoped ENIAC (Electronic Numerical Integrator and Computer), one of the earliest computers, could help with the war effort. With little guidance, no instructions, and barely any access to the machine itself, Betty, Jean, and Kay used mathematics, electrical engineering, logic, and common sense to command a computer as large as a room and create the modern world. The machine was like Betty, requiring outside-the-box thinking, like Jean, persistent and consistent, and like Kay, no mistakes, every answer perfect. Today computers are all around us, performing every conceivable task, thanks, in large part, to Betty, Jean, and Kay's pioneering work. Instructions Not Included is their story. This fascinating chapter in history is brought to life with vivid prose by Tami Lewis Brown and Debbie Loren Dunn and with striking illustrations by Chelsea Beck. Detailed back matter including historical photos provides a closer look.