Analysis of variance (ANOVA) is a statistical technique used to compare two or more groups of numbers to see if they are different from one another. For example, if you wanted to know if boys and girls have different heights, you could use ANOVA to figure it out. ANOVA looks at the mean (average) and the variance (how spread out the numbers are) between the two groups. If the average heights of boys and girls are different and the variance between the two groups is large, then the ANOVA will tell you that the two groups are different.