Welcome to the ESO Leaderboards overview page. On this page you can find the top scores of each trial and arena. The stats on the leaderboard page here are tracked via an addon, therefore it might take a while for them to update. The leaderboards scores that are listed here are from PC EU/NA. Console leaderboards are missing because we can't pull data via an addon on console.
Each leaderboard score has the account name, character name, class, alliance and score attached to it. The leaderboard scores are also listed up individually on each of the trial/arena overview pages.
The leaderboard contains the list of the highest scoring characters, therefore it is possible to see the same account name several times, but with different characters. There are several things that impact your score on the leaderboard. Time spent for completing the activity, amount of deaths, killed monsters, amount of sigils used, difficulty modes such as hardmode if available all have an impact on your score.