| FACTOR B | ||||||||
| B1 | B2 | Row Mean | ||||||
| FACTOR A | A1 |
|
1 | |||||
| A2 | 5 | |||||||
| Column Mean | 5 | 1 | ||||||

Factor A has an effect on the dependent variable (DV) when averaged over both levels of Factor B (different row means in table; non-flat, dashed red line in left graph).
Factor B has an effect on the dependent variable (DV) when averaged over both levels of Factor A (different column means in table; non-flat, dashed blue line in right graph).
The effect of Factor A depends on the level of Factor B; its effect is different at B1 than at B2 (left graph). Alternatively, the effect of Factor B depends on the level of Factor A; its effect is different at A1 than at A2 (right graph).