Empty and loading states

What this means

A loading state appears while data is being fetched. An empty state appears when loading is finished but there is nothing to show.

In beginner terms, this topic answers one practical question: "What should I write, and why does React care about it?" Do not try to memorize the syntax first. First understand the idea, then connect the syntax to that idea.

Why it matters

Beginners often build only the happy path. Real apps need to explain what is happening when data is missing, slow, or empty.

When you build real React screens, this idea helps you decide where data should live, what the user should see, and what should happen after an interaction. That is why this lesson is part of the main path instead of being an optional detail.

Step by step

1. Notice the UI problem this topic solves. 2. Look at the smallest possible example. 3. Change one value and predict what should appear. 4. Run the example and compare the result with your prediction. 5. Use the practice task before moving on.

Small example

if (isLoading) return <p>Loading lessons...</p>;
if (!lessons.length) return <p>No lessons yet.</p>;

Common mistake

Do not show a blank screen while waiting. Blank screens feel broken.

Practice task

Write loading, empty, and ready messages for a list of tasks.

Remember this

Every data screen needs loading, empty, and ready states.