Python dict() Function is used to create a Python dictionary. A dictionary is a collection of key-value pairs. A dictionary is a mutable data structure i.e. the data in the dictionary can be modified. In python 3.6 and earlier version dictionary is an unordered collection of key-value pairs but from python 3.7 dictionary is ordered data structure. Dictionary is an indexed data structure i.e. the contents of a dictionary can be accessed by using indexes, here in the dictionary the key is used as an index.

Python's dict() function is a built-in function that creates a new dictionary object. A dictionary in Python is an unordered collection of key-value pairs, where each key maps to a value.

The dict() function can be used in several ways. One way is to create a dictionary with key-value pairs. You can do this by passing a sequence of key-value pairs as arguments to the dict() function. For example: 

my_dict = dict([('apple', 1), ('banana', 2), ('orange', 3)])

This creates a dictionary with three key-value pairs: 'apple' maps to 1, 'banana' maps to 2, and 'orange' maps to 3.

Another way to use the dict() function is to create a dictionary with keyword arguments. For example: 

my_dict = dict(apple=1, banana=2, orange=3)

This creates the same dictionary as the previous example, but using keyword arguments instead of a sequence of key-value pairs.

You can also use the dict() function to create an empty dictionary: 

my_dict = dict()

This creates an empty dictionary that can be populated with key-value pairs later.

Overall, the dict() function is a useful tool for working with dictionaries in Python.