of python programs that really use for instancethe text editor and clock guis that we'll meet here are day-to-day workhorses on my machines because they are written in python and tkinterthey work unchanged on my windows and linux machinesand they should work on macs too since these are pure python scriptstheir future evolution is entirely up to their users-once you get handle on tkinter interfaceschanging or augmenting the behavior of such programs by editing their python code is snap although some of these examples are similar to commercially available programs ( pyedit is reminiscent of the windows notepad accessory)the portability and almost infinite configurability of python scripts can be decided advantage examples in other later in the bookwe'll meet other tkinter gui programs that put good face on specific application domains for instancethe following larger gui examples show up in later alsopymailgui comprehensive email client (pyform (mostly externalpersistent object table viewer (pytree (mostly externaltree data structure viewer and pycalc customizable calculator widget (smaller examplesincluding ftp and file-transfer guispop up in the internet part as well most of these programs see regular action on my desktoptoo because gui libraries are general-purpose toolsthere are very few domains that cannot benefit from an easy-to-useeasy-to-programand widely portable user interface coded in python and tkinter beyond the examples in this bookyou can also find higher-level gui toolkits for pythonsuch as the pmwtixand ttk packages introduced in some such systems build upon tkinter to provide compound components such as notebook tabbed widgetstree viewsand balloon pop-up help in the next part of the bookwe'll also explore programs that build user interfaces in web browsersinstead of tkinter-- very different way of approaching the user interface experience although web browser interfaces have been historically limited in functionality and slowed by network latencywhen combined with the rich internet application (riatoolkits mentioned at the start of browser-based guis today complete gui programs