The processes of welding are explained thoroughly in this elaborative book. Although there is a broad range of available literature on welding processes, a demand still exists to regularly update the engineering community on advancements in joining techniques of similar and dissimilar materials, in their numerical modelling, as well as in their sensing and control. This book has been compiled by a group of authors from different countries across five continents who joined hands to co-author this book on welding processes, giving detailed insight to the reader. Some of the main topics discussed here are sensing of welding procedures, welding of laser and numerical modelling.