| A | B |
| numerator | top number of a fraction |
| denominator | bottom number of a fraction |
| proper fraction | fraction with numerator smaller than denominator |
| improper fraction | fraction with numerator larger than denominator |
| mixed number | whole number written next to fraction |
| common fraction | fraction that has been reduced as much as possible |
| reciprocal | "upside-down" fraction; fraction with numerator and denominator switched |
| fraction bar | indicates division |
| decimal fraction | number written in base-10, decimal form |
| rational number | number that can be written in fraction form |