The difference can definitely be confusing. There are differences on a few different levels. First, an ANOVA is different from both a MANOVA and MANCOVA because an ANOVA has only one dependent variable, while both a MANOVA and MANCOVA have multiple dependent variables. An ANOVA typically compares a continuous (a.k.a interval or scale variable) between multiple independent groups of responses (usually 3 or more groups).

By contrast, both a MANOVA and MANCOVA have multiple dependent variables, but there are differences between the two as well. The difference between a MANOVA and MANCOVA lies in the number of independent variables. A MANOVA, like an ANOVA, has only one independent variable (which is typically a categorical variable that represents independent groups) and compares multiple dependent variables between independent groups.  A MANCOVA is a similar concept to MANOVA, except it allow for multiple independent variables (a.k.a. covariates).

In a MANCOVA, one is able to examine  multiple dependent variables for differences between independent groups, while controlling for other variables that may also be related to the DV. These covariates may be either categorical or continuous. I hope this helps, Eric! Please keep the questions coming!

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