Despite being 2000 years old cryptography is still a very active field of research. New needs and application fields like privacy the Internet of Things (IoT) physically unclonable functions (PUFs) post-quantum cryptography and quantum key distribution will keep fueling the work in this field. This book discusses quantum cryptography lightweight cryptography for IoT PUFs cryptanalysis and more. It provides a snapshot of some recent research results in the field providing readers with some useful tools and stimulating new ideas and applications for future investigation.