Significant Figures

To determine the number of significant figures in a measurement, follow these rules:

1. All non-zero digits are significant
2. Zeros between non-zero digits are significant
3. Leading zeros are not significant
4. Trailing zeros after a decimal point are significant
5. Trailing zeros in a whole number are significant only if there's a decimal point

For example:
- 1234 has 4 significant figures
- 1.234 has 4 significant figures
- 0.00123 has 3 significant figures
- 1.2300 has 5 significant figures