C# Fundamentals · Arrays & Methods · Lesson 18 of 22

Lists

Concept

Lists

Unlike arrays, a List<T> can grow and shrink at runtime, with methods like .Add() and .Remove() for managing its elements.

By the end of this lesson

Explain the core idea behind Lists.
Predict output before running a change.
Test one realistic and one unusual input.
Use the result to make the next decision.

How to study this page

1. Read one concept.
2. Change the example.
3. Run, compare, and explain.
4. Complete the challenge below.

ExampleRunnable

using System.Collections.Generic;

List<string> names = new List<string>();
names.Add("Alex");
Console.WriteLine(names[0]);

Try it Yourself »

Self-check before continuing

Without looking at the example, describe what changes when you modify one input in Lists. Then reopen the editor and prove your explanation with a small test.

You are ready to continue when you can predict, test, and explain the result.

Your turn

Create a List<string> of 3 course names and print the second one.

Loading editor…

Console

Output will appear here...