Acknowledgement: From Summer 2005 to Fal 2010, Amit Chakrabarti was supported in part by a CAREER Award; from the NSF. Course notes for "Lower Bounds in Computer Science" and "Data Stream Algorithms" are available at the websites for the respective courses, for the use of students and instructors worldwide. These notes were started during the period of the CAREER Award, and NSF's support is gratefully acknowledged.