Python lists

A Python list is a built-in function that helps organize heterogeneous data. If you’re learning the basics of Python, learning Python lists is extremely important. Python lists are ordered, meaning that items maintain their position in the list and are mutable, allowing for the modification of their content. These lists can contain any type of data—including integers, strings, and even other lists—and they support a variety of operations, such as appending items, slicing, sorting, and more.

Their dynamic nature makes them a fundamental tool in Python programming for tasks ranging from simple data aggregation to complex data structures and algorithms.

Characteristics of Python lists

  • Duplication: Python lists can have duplicate elements. The exact value can appear multiple times in a list.

  • Dynamic array structure: Lists in Python are implemented as dynamic arrays, which means they can grow or shrink in size as needed.

  • Ordered collection: The elements in a list maintain their order. The first element you put in is the first element in the list, and so on.

  • Mutable: Lists are mutable, allowing for the modification of their content. You can alter, add, and remove items in a list after creation.

  • Heterogeneous elements: A list can contain items of different data types, including numbers, strings, other lists, and more complex objects.

  • Nested lists: Lists can contain other lists as their elements, which is useful for creating matrices or multidimensional arrays.

  • Variable length: Lists are not fixed in size. You can start with an empty list and add or remove elements from a populated list.

Python list rules

  1. The order of the list does not change. The order will remain the same when inserting elements into a list.

  2. You can access list elements using their index, starting from 0 for the first element.

  3. Lists can contain other lists as elements, which allows for the creation of nested or multidimensional lists.

  4. Python provides a concise syntax to create lists from existing iterables in a single line of code, which we call list comprehensions.

  5.  A list does not have a fixed size. You can continually add or remove elements.