We have to start by thanking almighty for his blessings that this book has been completed in time. We helped by our parents, teachers, colleagues and students too many names but are very special who have assisted our thinking by for this new edition by providing challenging comments and questions.So many people have helped us out that it is unfortunately no longer feasible to list all their names but we are always thankful to them. This image notwithstanding, we have tried to pack into this first edition as many fascinating new topics like introduction to internet of things (IoT), applications IoT characteristics of IoT, IoT architecture and protocols, physical design/local design of IoT, understanding basics of Arduino IDE, installation and understanding basics of Arduino IDE, basic of C language using Arduino IDE, loops and control statement practical, arrays and function, practical using Arduino-interfacing sensors. We have also received extraordinary help form AICTE New Delhi, HPTU Hamirpur, NIT Hamirpur, IIT Mandi, RGPV Bhopal, MANIT, NITTTR Bhopal, Panjab University Chandigarh, NIFT Kannur Kerala, Teaching, Non-Teaching staff and students of B.Tech(CSE) and MCA Himachal Pradesh University, Shimla,Principal cum Director and other officers/ employees of Govt. P.G. College, Dharamshala, H.P. Our special thanks are due to all the faculty members and non-teaching staff of School of Computer Science & Engineering, Department of B.Tech (CSE) and MCA, Govt. P.G. College, Dharamshala. We also thank students of B.Tech (CSE) and MCA department in batches 2015 to 2020 have given us numerous ideas. Finally,we would like to thanks to Satya Prakashan for bringing out this book in such a nice form. Thank you so much everyone!!!!!! Dr. Pawan Thakur Ms. Susheela Pathania