| Data Type | Definition | Key Operations | Example |
|---|---|---|---|
| Nominal | Categorical data with no order. | Counting frequencies. | Genders, hair color, car brands. |
| Ordinal | Categorical data with a rank or order. | Ranking, mode, median. | Satisfaction ratings, military ranks. |
| Interval | Ordered data with equal intervals. No true zero. | Addition and subtraction. | Temperature in °C/°F, years. |
| Ratio | Ordered data with equal intervals and a true zero. | All mathematical operations. | Height, weight, age, income. |