Explain a Complex Wikipedia Article in Under 150 Words

You looked something up and the Wikipedia article answered your question with twelve more questions. This extracts what you actually need to know: what it is, why it matters, one real-world example. Under 150 words. You can move on now.

Read the Wikipedia article text below and explain the subject to someone who has no background in the topic. Your explanation must:
- Fit in 150 words or fewer
- Avoid unexplained jargon
- Cover: what it is, why it matters, and one real-world example
- Not begin with 'This is' or a dictionary-style definition

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{WIKIPEDIA_TEXT}
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