So last week my boyfriend called me from the supermarket and was wondering about the difference between jelly and jam. We ultimately decided that it didn't matter; honestly, I don't know which he got, because I don't eat jelly/jam/whatever as much as he does. Shucks, for you guys, I'll go check.
Well I'll be damned; he got preserves. But the conversation stands. I didn't know, so naturally I looked it up on the Wik'. I'm going to gloss over the regional differences (I don't know, British people... I just don't know), and go directly to the culinary definitions.
Jelly refers to a fruit spread made out of fruit juice; jam includes the fruit's flesh. And, in case you're wondering, "the term Preserves is usually interchangeable with Jam, however some cookbooks define Preserves as cooked and gelled whole fruit (or vegetable), which includes a significant portion of the fruit." So preserves (screw you, arbitrary uppercase) is just extra-fleshy jam. Yum. There's also other fun spreadables listed in the article, like confit. Fancy-shmancy!