Explain What an Emergency Fund Is and Why You Need One

You'd rather be investing than parking cash that just sits there, and then the boiler packs in. This prompt explains in plain terms what an emergency fund is, how big it should be, where to keep it, and what counts as a real emergency versus a bill you should have seen coming. Good for anyone building financial resilience from the ground up.

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Financial resilience begins with a cash buffer that covers unexpected expenses without triggering debt. Many people skip this step in favour of investing, then find one car repair or medical bill undoes months of progress.
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<task>
Write a plain-language explanation of what an emergency fund is, how large it should be, where to keep it, and what counts as an emergency versus a predictable expense.
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<output_format>
Four short paragraphs: What It Is, How Much (with a beginner-friendly rule of thumb), Where to Keep It, and What Counts as an Emergency (with two examples of what does and does not qualify). Under 250 words. Friendly, non-preachy tone.
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