Hey there. I would like to ask a question because i don't understand some things with mmo.
I believe i can play as a single player,,,Correct me if im wrong...
So lets say there is another person and lets call him jeff.jeff logs in, also as a single player , and starts a quest...he is in a fight with his lets say fifth monster and halfway the quest. Then i log in to elderscrolls
online.....Does this mean that i jump in the quest halfway with that other guy ??

No, each player will have his or her quest progress saved, and won't ever be influenced by other players unless you join in a group with them. The only kind of influence another player can have on your quests without being in a group is killing a certain monster/taking a certain item needed for a quest, and you possibly having to wait for the monster to respawn.

a lot of game companies are leaning towards instanced areas for the main story line to prevent people from "getting in your way" cause like archie said, if you need to kill 10 of a certain mob there could already be 4 or 5 people there doing the same quest and you all end up fighting for the spawns. this is the worst at the start of an mmo or xpac launch when everyone is leveling together. not sure what the stance is on instanced areas in this game is though