Lists and Keys
Turn an array into elements with .map(). Give every item a stable, unique key so React can track it between renders.
Examplereact
Use an id from your data as the key, not the array index when items can be reordered or removed. Notice filter creates a new array: never modify state arrays in place.
Quick check
What is the `key` prop for?
Finish the quick check (and any code exercise) to complete this lesson, or mark it done yourself.
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