Set items are among some of the many goodies you’ll be able to get in The Elder Scrolls Online. Like World of Warcraft and many other MMORPGs, the items you equip come in various forms, some of which are set items that provide additional set bonuses for being equipped simultaneously.
Interestingly enough, the system allows any class to equip any piece of item, so if you want to play a heavy, tank-like spellcaster, you can totally do that in The Elder Scrolls Online. And enabling you to play the character you want to play as is something these set items will do for you.
A redditor has posted some of the many set items that are, ahem, set for discovery in The Elder Scrolls Online once it releases on April 4, 2014.