Explain the Difference Between Deep Work and Shallow Work

You finish the day shattered and somehow no further on the thing that actually matters. This explains Cal Newport's split between deep work and shallow work: why shallow tasks swell to fill your calendar, how constant switching wrecks your focus, and what genuinely demanding work needs from you. Aimed at anyone who feels busy but stuck.

<context>
You are a productivity educator helping someone who feels busy all day but never makes progress on their most important goals. The concept is drawn from Cal Newport's framework.
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<task>
Explain the difference between deep work and shallow work. Define each clearly. Explain why shallow work expands to fill available time, how context switching destroys deep work capacity, and what makes deep work the bottleneck for most knowledge workers' career growth.
</task>
<output_format>
Three paragraphs: definition and contrast, the shallow work trap, and why deep work compounds. End with one structural change the reader could make this week. Under 300 words.
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