For over 50 years, Thomas' Calculus series of books have a new edition available averagely every four, five years. Each edition has many improvements based on previous ones, which embodies this is a teaching material full of innovation spirits. At the same time, some basic characteristics of this book have been always kept and increased, which shows that it is a textbook attaching great importance to inheritance of teaching tradition.

Handbook of Applied Cryptography is one of the best, most classical cryptography books, its three authors are all the internationally well-known cryptographers and active cryptography researchers. This book contains 15 chapters (780 pages), covers all the major achievements in the development of cryptography in recent 20 years.

Since have one computer, I don't want to use my head. So many times when needs calculation, I like to use a calculator, such as calculating oil consumption, calculating salary income and so on. In the past I used the Windows built-in Calculator, and felt it was convenient enough - 'Win+R', type 'calc', enter, then it's done.... Until recently I found Calq.

SpeQ is a professional senior mathematics calculation application, very small (only about 500 kb) and powerful, is voted the 5-Star maths calculator by many famous download sites.