Squeak is a modern open-source development environment for the classic Smalltalk-80 programming language. Despite being the first purely object-oriented language and environment, Smalltalk is in many ways still far ahead of its successors in promoting a vision of an environment where everything is an object, and anything can change at run-time.

The goal of this book is to teach you to think like a computer scientist. This way of thinking combines some of the best features of mathematics, engineering, and natural science. Like mathematicians, computer scientists use formal languages to denote ideas (specifically computations). Like engineers, they design things, assembling components into systems and evaluating tradeoffs among alternatives. Like scientists, they observe the behavior of complex systems, form hypotheses, and test predictions.

Think Stats is an introduction to Probability and Statistics for Python programmers.

*Think Stats emphasizes simple techniques you can use to explore real data sets and answer interesting questions. The book presents a case study using data from the National Institutes of Health. Readers are encouraged to work on a project with real datasets.
*If you have basic skills in Python, you can use them to learn concepts in probability and statistics. Think Stats is based on a Python library for probability distributions (PMFs and CDFs). Many of the exercises use short programs to run experiments and help readers develop understanding.

XForms is a World Wide Web Consortium recommendation for creating web forms and web applications. XForms is easy to learn, provides a rich user experience and does not require you to learn JavaScript. There are many different implementations of XForms and this cookbook is designed to work with any of them. A list of implementations is available on the W3C web site.

eXtensible Markup Language (XML) is a widely used computer language for creating and designing pages on the World Wide Web, and for defining other languages with more specialized purposes. This Wikibook provides a detailed description of XML, its origins, its programming, and its uses on the Internet today. This book also provides exercises with which to test the knowledge you have gained through the deliberate study of its contents.