this part' begin at the bottom--exploring both built-in objects and the expressions you can code to use them we'll move on to study statements in the next part of the bookthough we will find that they largely exist to manage the objects we'll meet here moreoverby the time we reach classes in the oop part of this bookwe'll discover that they allow us to define new object types of our ownby both using and emulating the object types we will explore here because of all thisbuilt-in objects are mandatory point of embarkation for all python journeys traditional introductions to programming often stress its three pillars of sequence ("do thisthen that")selection ("do this if that is true")and repetition ("do this many times"python has tools in all three categoriesalong with some for definition--of functions and classes these themes may help you organize your thinking early onbut they are bit artificial and simplistic expressions such as comprehensionsfor exampleare both repetition and selectionsome of these terms have other meanings in pythonand many later concepts won' seem to fit this mold at all in pythonthe more strongly unifying principle is objectsand what we can do with them to see whyread on why use built-in typesif you've used lower-level languages such as or ++you know that much of your work centers on implementing objects--also known as data structures--to represent the components in your application' domain you need to lay out memory structuresmanage memory allocationimplement search and access routinesand so on these chores are about as tedious (and error-proneas they soundand they usually distract from your program' real goals in typical python programsmost of this grunt work goes away because python provides powerful object types as an intrinsic part of the languagethere' usually no need to code object implementations before you start solving problems in factunless you have need for special processing that built-in types don' provideyou're almost always better off using built-in object instead of implementing your own here are some reasons whybuilt-in objects make programs easy to write for simple tasksbuilt-in types are often all you need to represent the structure of problem domains because you get powerful tools such as collections (listsand search tables (dictionariesfor freeyou can use them immediately you can get lot of work done with python' builtin object types alone built-in objects are components of extensions for more complex tasksyou may need to provide your own objects using python classes or language inter introducing python object types