Lists

A list stores values in order.

Output:

[8, 6, 9]

Lists are useful when order matters or when you need to process several values one by one.

Iterating Over a List

Use a for loop to visit each item:

Output:

8
6
9

The loop variable score refers to one value at a time.

Appending Values

append() adds one item to the end:

Output:

[8, 6, 9]

This pattern is common when a program builds a result gradually.

Build a list

The list starts empty and grows one item at a time.

Runs locally with Python in your browser.

Ready to run.

Lists Can Hold Any Values

Lists can hold strings:

tokens = ["large", "language", "model"]

They can also hold records:

Later, we will usually prefer dictionaries or dataclasses for named records. For now, notice that a list can hold other lists.

Lists Keep Order and Duplicates

Do not name a list as if it were one item:

score = [8, 6, 9]

This works, but scores is clearer because the value holds several scores.

Exercise: Append one value

What does this program print?

Answer it first, then check.

HintKeep the existing items

append() changes the list by adding one item at its end.

SolutionSix is appended

The list begins as [2, 4]. After values.append(6), it is [2, 4, 6], which is what Python prints.

Lists Store Sequences You Can Change

Use a list when you have several values and their order is meaningful.