Decimal
A number written with a decimal point, like 0.75 or 3.14.
- Base-10 representation of fractions.
- Some fractions repeat forever (e.g., 1/3 = 0.333...).
- Float storage causes 0.1 + 0.2 ≠ 0.3.
When to use: Reporting probabilities, weights, learning rates, losses.
Example: lr = 0.001, dropout = 0.2, accuracy = 0.9542 - all decimals (stored as floats).