* kilo (k): means 1000 (10³)
* hecto (h): means 100 (10²)
* deka (da): means 10 (10¹)
* deci (d): means 0.1 (10⁻¹)
* centi (c): means 0.01 (10⁻²)
* milli (m): means 0.001 (10⁻³)
While other prefixes exist (like mega, micro, etc.), these are the most commonly encountered and emphasized at the middle school level. The focus is usually on understanding the relationships between them and converting between units (e.g., kilometers to meters).