1 2 .. _library-intro: 3 4 ************ 5 Introduction 6 ************ 7 8 The "Python library" contains several different kinds of components. 9 10 It contains data types that would normally be considered part of the "core" of a 11 language, such as numbers and lists. For these types, the Python language core 12 defines the form of literals and places some constraints on their semantics, but 13 does not fully define the semantics. (On the other hand, the language core does 14 define syntactic properties like the spelling and priorities of operators.) 15 16 The library also contains built-in functions and exceptions --- objects that can 17 be used by all Python code without the need of an :keyword:`import` statement. 18 Some of these are defined by the core language, but many are not essential for 19 the core semantics and are only described here. 20 21 The bulk of the library, however, consists of a collection of modules. There are 22 many ways to dissect this collection. Some modules are written in C and built 23 in to the Python interpreter; others are written in Python and imported in 24 source form. Some modules provide interfaces that are highly specific to 25 Python, like printing a stack trace; some provide interfaces that are specific 26 to particular operating systems, such as access to specific hardware; others 27 provide interfaces that are specific to a particular application domain, like 28 the World Wide Web. Some modules are available in all versions and ports of 29 Python; others are only available when the underlying system supports or 30 requires them; yet others are available only when a particular configuration 31 option was chosen at the time when Python was compiled and installed. 32 33 This manual is organized "from the inside out:" it first describes the built-in 34 data types, then the built-in functions and exceptions, and finally the modules, 35 grouped in chapters of related modules. The ordering of the chapters as well as 36 the ordering of the modules within each chapter is roughly from most relevant to 37 least important. 38 39 This means that if you start reading this manual from the start, and skip to the 40 next chapter when you get bored, you will get a reasonable overview of the 41 available modules and application areas that are supported by the Python 42 library. Of course, you don't *have* to read it like a novel --- you can also 43 browse the table of contents (in front of the manual), or look for a specific 44 function, module or term in the index (in the back). And finally, if you enjoy 45 learning about random subjects, you choose a random page number (see module 46 :mod:`random`) and read a section or two. Regardless of the order in which you 47 read the sections of this manual, it helps to start with chapter 48 :ref:`built-in-funcs`, as the remainder of the manual assumes familiarity with 49 this material. 50 51 Let the show begin! 52 53
