---
title: "Lists: Many Values Under One Name"
description: "Holding a whole collection of values in a single variable, then reading and changing items by their position."
canonical: https://lightmysky.com/learn/computing/lists-many-values-under-one-name-mt_ipB6kmyK85
source: https://lightmysky.com/learn/computing/lists-many-values-under-one-name-mt_ipB6kmyK85.md
retrieved: 2026-11-12
---

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# Lists: Many Values Under One Name

Holding a whole collection of values in a single variable, then reading and changing items by their position.

Subject: Computing · Area: Programming · Ages 15 to 16
Page: https://lightmysky.com/learn/computing/lists-many-values-under-one-name-mt_ipB6kmyK85

## Ready when they can

- Create a list and read an item by its index
- Add and remove items, and say how the positions shift
- Explain why one list beats twenty separate variables for the same data

## Lesson: Many values, one name

One variable can hold a whole row of values called a list. A list of rainbow colours holds red, orange, yellow, green, blue, indigo and violet under a single name. That beats juggling seven separate variables.

**Example.** Each slot has a seat number starting at 0. rainbowColours[0] gives red and rainbowColours[6] gives violet. Watch your seats, since off-by-one slips love list code.

You can rewrite any slot by its seat, so rainbowColours[4] = "cyan" swaps blue for cyan. To grow the end you append. On an empty chore list, chores.append("Wash the dishes"), then "Do laundry", then "Mow the lawn" fill the next free seats: 0, 1 and 2. Slipping one in earlier with insert() pushes every later slot one seat up.

**Tip.** Pick one list over twenty loose variables whenever the values belong together. One name then holds the whole set.

**Recap.** A list stores many values under one name, and you read, rewrite and grow slots by their seat numbers.

## Practice

8 questions on this page, each with its working shown.

## Needs first

- [Strings: Indexing, Slicing and Length](https://lightmysky.com/learn/computing/strings-indexing-slicing-and-length-mt_33hA050_Qz)

## Opens up

- [Binary Search on Sorted Data](https://lightmysky.com/learn/computing/binary-search-on-sorted-data-mt_3avV-VasFZ)
- [Stacks: Last In, First Out](https://lightmysky.com/learn/computing/stacks-last-in-first-out-mt_Evw7zeJE6Q)
- [Data as a Matrix: Rows, Features and the Target](https://lightmysky.com/learn/computing/data-as-a-matrix-rows-features-and-the-target-mt_KEN-TU1Gpn)
- [Traversing a List to Build a Result](https://lightmysky.com/learn/computing/traversing-a-list-to-build-a-result-mt_lusbjHFt95)
- [Dictionaries: Values Found by Key](https://lightmysky.com/learn/computing/dictionaries-values-found-by-key-mt_mofpj0n5AM)