This link has good introduction to CMMI Levels – https://msdn.microsoft.com/cs-cz/library/ee461556(v=vs.100).aspx
Cisco has published few interesting pdfs about IoT (Internet of Things). This is a good starting point to understand the concept. See this link – http://www.cisco.com/c/en/us/solutions/internet-of-things/resources/case-studies.html
http://preparepm.com/notes/intro.html This link has notes on all topics and questions as well. http://www.project-management-skills.com/what-is-project-management.html This has explanation in detail.