The article discusses how Analysis of Variance (ANOVA) is used to compare three or more group means. ANOVA helps researchers test if there are differences between groups while controlling for the chance of making a mistake. By comparing variance estimates, ANOVA can determine if there is a treatment effect. It can also be used to study multiple treatment variables at once. While many researchers use ANOVA with post hoc comparisons, planned comparisons can be more useful if specific group differences are already known.