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In this stage, I introduced you to props.

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Props are a way to pass data from
one component to another in React.

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They allow us to customize and
configure components dynamically.

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By passing props, we can control the
behavior and appearance of our component.

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To use props in a component,

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we simply added a parameter named props to
the function representing the component.

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This props parameter allows us access to
the data passed from the parent component.

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We successfully passed props
to the Header, Item, and

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Counter components, allowing them
to receive and utilize the data.

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With the Item component now accepting
props, we were able to leverage

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the power of the map method to
generate a list of items efficiently.

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By iterating over an array of items,

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we dynamically created a list of Item
components based on the data provided.

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This approach enabled us to
scale our application easily,

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handling any number of items in the array.

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When creating lists of
components using map,

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React requires us to assign a unique
key prop to each component.

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The key prop helps React
efficiently update and

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manage the list of components
whenever changes occur.

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It's crucial to provide a stable and
unique identifier as a key prop,

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such as a unique ID
associated with each item.

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Our grocery list app is starting to
take shape, but it's still static.

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The items displayed never changes
because we're passing a static

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list of items to our app.

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And the counter doesn't
change an item's quantity.

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Remember, props are read-only.

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So in order to add dynamic behavior and
interactions,

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our app needs data that can change.

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A web application's UI is normally
a function of the data you put into it.

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In other words, changes in your
data result in changes to the UI.

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And when changes are made to the UI,
your data changes in response.

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In the next stage, we'll explore
the concept of state in React components.

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State allows us to store and

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manage information within a component
that can be altered over time.

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We'll learn how components, props, and

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state work together to build
interactive React applications.