What is a one way ANOVA?
A one-way ANOVA is an ANOVA where you have one independent variable that has more than two condition. For two or more independent variables, you would use a two-way ANOVA.
This is in contrast with a two-way ANOVA where you have two independent variables and each have multiple conditions.
For example, you would use a one-way ANOVA if you wanted to determine the effects of coffee brands on heart rate. Your independent variable is the coffee brand.
You would use a two-way ANOVA if you wanted to determine the effects of coffee brands and self-reported anxiety levels on heart rate. Your two independent variables are 1) coffee brand and 2) self-reported anxiety level.