browser what we won' cover now that 've told you what we will cover in this booki also want to be clear about what we won' cover like tkinterthe internet is vast topicand this part of the book is mostly an introduction to its core concepts and an exploration of representative tasks because there are so many internet-related modules and extensionsthis book does not attempt to serve as an exhaustive survey of the domain even in just python' own tool setthere are simply too many internet modules to include each in this text in any sort of useful fashion moreoverhigher-level tools like djangojythonand app engine are very large systems in their own rightand they are best dealt with in more focused documents because dedicated books on such topics are now availablewe'll merely scratch their surfaces here with brief survey later in this this book also says almost nothing about lower-level networking layers such as tcp/ip if you're curious about what happens on the internet at the bit-and-wire levelconsult good networking text for more details in other wordsthis part is not meant to be an exhaustive reference to internet and web programming with python-- topic which has evolved between prior editions of this bookand will undoubtedly continue to do so after this one is published insteadthe goal of this part of the book is to serve as tutorial introduction to the domain to help you get startedand to provide context and examples which will help you understand the documentation for tools you may wish to explore after mastering the fundamentals here other themes in this part of the book like the prior parts of the bookthis one has other agendastoo along the waythis part will also put to work many of the operating-system and gui interfaces we studied in parts ii and iii ( processesthreadssignalsand tkinterwe'll also get to see the python language applied in realistically scaled programsand we'll investigate some of the design choices and challenges that the internet presents that last statement merits few more words internet scriptinglike guisis one of the "sexierapplication domains for python as in gui workthere is an intangible but instant gratification in seeing python internet program ship information all over the world on the other handby its very naturenetwork programming can impose speed overheads and user interface limitations though it may not be fashionable stance these dayssome applications are still better off not being deployed on the web traditional "desktopgui like those of part iiifor examplecan combine the featurerichness and responsiveness of client-side libraries with the power of network access on the other handweb-based applications offer compelling benefits in portability and network scripting