They are separate (Destiny)

by Xenos , Shores of Time, Friday, October 31, 2014, 17:49 (3475 days ago) @ ckamp

Perhaps I need to reread the update, but I'm confused as to whether there are quests and story missions, or are the story missions just being told as quests now.

In the second answer he says "Without spoiling the details, Crota’s summoning is a multifaceted ritual that has implications for Story missions, Quests, the “Will of Crota” Strike, and the “Crota’s End” Raid." So they are listed as separate activities.