other tools other tools serve more specific roles among this crowd are mod_python-- system which optimizes the execution of python server-scripts in the apache web servertwisted--an asynchronousevent-drivennetworking framework written in pythonwith support for large number of network protocols and with precoded implementations of common network servershtmlgen-- lightweight tool that allows html code to be generated from tree of python objects that describes web pageand python server pages (psp)-- server-side templating technology that embeds python code inside htmlruns it with request context to render part of reply pageand is strongly reminiscent of phpaspand jsp as you might expect given the prominence of the webthere are more internet tools for python than we have space to discuss here for more on this frontsee the pypi website at are implemented using python' internet tools themselvesagainthe goal of this book is to cover the fundamentals in an in-depth wayso that you'll have the context needed to use tools like some of those above wellwhen you're ready to graduate to more comprehensive solutions as we'll seethe basic model of cgi scripting we'll meet here illustrates the mechanisms underlying all web developmentwhether it' implemented by bare-bones scriptsor advanced frameworks because we must walk before we can run wellthoughlet' start at the bottom hereand get handle on what the internet really is the internet today rests upon rich software stackwhile tools can hide some of its complexityprogramming it skillfully still requires knowledge of all its layers as we'll seedeploying python on the webespecially with higher-order web frameworks like those listed aboveis only possible because we truly are "surfing on the shoulders of giants plumbing the internet unless you've been living in cave for the last decade or twoyou are probably already familiar with the internetat least from user' perspective functionallywe use it as communication and information mediumby exchanging emailbrowsing web pagestransferring filesand so on technicallythe internet consists of many layers of abstraction and devices--from the actual wires used to send bits across the world to the web browser that grabs and renders those bits into textgraphicsand audio on your computer in this bookwe are primarily concerned with the programmer' interface to the internet thistooconsists of multiple layerssocketswhich are programmable interfaces to the low-level connections between machinesand standard protocolswhich add network scripting