The evaluation modes can be set individually for each round and collection in their settings. The round and collection settings can be accessed via the small gear icon that appears when you hover the elements of the sidebar at the left.
Simple voting allows you to vote for the best submissions. Votes of all jury members are summarized. Recommended for simple evaluations, especially in early rounds. The managers see how many votes a submission has received by the jury and jurors can see for which submissions they personally voted.
With Five-Star rating you rate submissions on a scale from 1 star (worst) to 5 stars (best). An average rating from all jury members is calculated and visible to managers. Recommended for precise evaluations. You can also switch from the average calculation to a sum of voted stars.
Tip: You can set filters to find the submissions with the best ratings or most votes.