ANOVA (short for “Analysis of Variance”) is a family of statistical tests for testing if 3 or more means are (all) equal.
The most common scenario tests if 3(+) groups of cases have similar mean scores on a single variable. This test is known as a one-way ANOVA.
Another basic scenario is testing whether 1 group of cases have similar means on 3(+) variables. This is known as a repeated measures ANOVA.
Last, we can compare means for multiple factors (defining either groups of cases or variables) simultaneously. We now speak of a factorial ANOVA. The simplest factorial ANOVA is a two way ANOVA which examines how two factors affect one outcome variable.