all data types in python are objects in factpretty much everything is an object in pythonincluding modulesclassesand functionsas well as literals such as strings and integers each object in python has typea valueand an identity when we write greet "hello worldwe are creating an instance of string object with the value "hello worldand the identity of greet the identity of an object acts as pointer to the object' location in memory the type of an objectalso known as the object' classdescribes the object' internal representation as well as the methods and operations it supports once an instance of an object is createdits identity and type cannot be changed we can get the identity of an object by using the built-in function id(this returns an identifying integer and on most systems this refers to its memory locationalthough you should not rely on this in any of your code alsothere are number of ways to compare objectsfor exampleif = # and have the same value if is bif and are the same object if type(ais type( ) and are the same type an important distinction needs to be made between mutable and immutable objects mutable object' such as lists can have their values changed they have methodssuch as insert(or append()that change an objects value immutable objectssuch as stringscannot have their values changedso when we run their methodsthey simply return value rather than change the value of an underlying object we canof courseuse this value by assigning it to variable or using it as an argument in function strings strings are immutable sequence objectswith each character representing an element in the sequence as with all objectswe use methods to perform operations stringsbeing immutabledo not change the instanceeach method simply returns value this value can be stored as another variable or given as an argument to function or method