ANOVA (analysis of variance) is a statistical technique used to compare differences between group means. It involves calculating the F ratio, which is the ratio of variance between groups to variance within groups. If the calculated F value is greater than the critical F value from statistical tables, then the difference between group means is considered statistically significant. The document provides steps for conducting a one-way ANOVA, including calculating sums of squares, mean squares, and the F ratio to determine if differences between three varieties of wheat are statistically significant based on per acre production data.