Kurtosis measures 'tailedness' and peakedness of distribution. Kurtosis = Σ(xi - x̄)⁴/(nσ⁴). Types: Mesokurtic (normal, k=3); Leptokurtic (peaked, k>3, heavy tails); Platykurtic (flat, k<3, light tails). Excess kurtosis = Kurtosis - 3. Interpretation: High kurtosis → extreme values more likely. Low kurtosis → uniform distribution. Example: Stock returns. Normal distribution k=3. Crypto returns k=8 (leptokurtic, more extreme swings). Exam tip: Understand how kurtosis affects probability of extreme events. Recognize distribution types. Practice: Calculate and interpret for risk assessment.