Python Lists: A Complete Beginner Guide

A natural way to organize and store data is in a list. Some languages call them “arrays”, but in Python we just call them lists. Think of all the apps you use and how many of the items in them are organized into lists — a social media feed is a list of posts, an online store is a list of products, the state of a chess game is a list of moves.

All the content from our Boot.dev courses are available for free here on the blog. This one is the “Lists” chapter of Learn to Code in Python. If you want to try the far more immersive version of the course, do check it out!

How Do You Create a List in Python?

Lists are declared using square brackets, with commas separating each item:

inventory = ["Iron Breastplate", "Healing Potion", "Leather Scraps"]

Lists can contain items of any data type. When a list gets long, you can break it across multiple lines for readability:

flower_types = [
    "daffodil",
    "rose",
    "chrysanthemum",
]

This is just a styling change — the code runs the same either way. You can also start with an empty list and fill it later:

cards = []

Note: If you’re coming from another language and searching for “Python arrays” — you’re in the right place. Python’s list is the equivalent of arrays in most other languages.

How Does List Indexing Work in Python?

Each item in a list has an index — a number that refers to its position. Indexes start at 0, not 1:

names = ["Bob", "Lane", "Alice", "Breanna"]

You access items by their index using bracket notation:

best_languages = ["JavaScript", "Go", "Rust", "Python", "C"]
print(best_languages[1])  # Go

You can also update an item at a given index:

inventory = ["Leather", "Iron Ore", "Healing Potion"]
inventory[0] = "Leather Armor"
# ['Leather Armor', 'Iron Ore', 'Healing Potion']

Negative indexes count from the end: my_list[-1] gives you the last item, my_list[-2] gives the second to last, and so on.

How Do You Get the Length of a List?

The len() function returns how many items are in a list:

fruits = ["apple", "banana", "pear"]
length = len(fruits)  # 3

The length is always one greater than the last index, because indexing starts at 0. This is useful when you need the last index: it’s always len(my_list) - 1.

How Do You Add Items to a List?

The .append() method adds a single item to the end of a list:

cards = []
cards.append("nvidia")
cards.append("amd")
# ['nvidia', 'amd']

It’s common to create an empty list then fill it with values using a loop. You can also combine two lists using the + operator:

total = [1, 2, 3] + [4, 5, 6]
print(total)  # [1, 2, 3, 4, 5, 6]

How Do You Remove Items From a List?

The .pop() method removes the last element from a list and returns it:

vegetables = ["broccoli", "cabbage", "kale", "tomato"]
last = vegetables.pop()
# vegetables = ['broccoli', 'cabbage', 'kale']
# last = 'tomato'

You can also pass an index to .pop() to remove an item at a specific position: vegetables.pop(1) would remove "cabbage".

The del keyword deletes items by index or slice:

nums = [1, 2, 3, 4, 5, 6, 7, 8, 9]
del nums[3]    # [1, 2, 3, 5, 6, 7, 8, 9]
del nums[1:3]  # [1, 5, 6, 7, 8, 9]

To check if an item exists before removing it, use the in keyword:

fruits = ["apple", "orange", "banana"]
print("banana" in fruits)  # True

How Do You Loop Over a List in Python?

You can loop over a list using an index with range() and len():

sports = ["soccer", "basketball", "baseball"]
for i in range(0, len(sports)):
    print(sports[i])

But Python has a much cleaner syntax when you don’t need the index — just iterate directly over the items:

trees = ["oak", "pine", "maple"]
for tree in trees:
    print(tree)
# oak
# pine
# maple

The variable tree takes on each value in the list directly, no index needed. This is the preferred style in Python when you only need to read the values.

How Does List Slicing Work in Python?

Python’s slicing operator lets you grab a section of a list. It returns a new list:

my_list[start:stop:step]

All three sections are optional:

numbers = [0, 1, 2, 3, 4, 5, 6, 7, 8, 9]
numbers[:3]   # [0, 1, 2]
numbers[3:]   # [3, 4, 5, 6, 7, 8, 9]
numbers[::2]  # [0, 2, 4, 6, 8]
numbers[-3:]  # [7, 8, 9]

Like range(), the start is inclusive and stop is exclusive. You can reverse a list with a negative step:

numbers = [1, 2, 3, 4, 5]
reversed_numbers = numbers[::-1]  # [5, 4, 3, 2, 1]

What Is a Tuple in Python?

Tuples are like lists but immutable — once created, you can’t change them. They’re declared with parentheses:

my_tuple = ("this is a tuple", 45, True)
print(my_tuple[0])  # this is a tuple
print(my_tuple[1])  # 45

Tuples are great for small, fixed groups of data — like a name and age pair:

dog = ("Fido", 4)
dog_name, dog_age = dog
print(dog_name)  # Fido
print(dog_age)   # 4

That second example uses tuple unpacking to assign each value to its own variable. When you return multiple values from a function, you’re actually returning a tuple.

For single-item tuples, you need a trailing comma so Python doesn’t treat the parentheses as grouping:

single = ("Fido",)

What Should You Learn After Python Lists?

Lists are used everywhere in Python, so now is a great time to get comfortable with loops and conditionals if you haven’t already — they’re what make lists truly powerful. From here, most beginners move on to dictionaries (another core data structure) and string manipulation.

If you want to keep going through the full Python curriculum with hands-on exercises, check out the Learn to Code in Python course on Boot.dev.