WIP! ヾ(•ω•`)o i am currently editing this webpage!
Jpop is.... Japanese pop! And Jrock is.................... Japanese rock!!!! However, on this page, I'm going to refer to both as Jpop for the sake of being concise, and because there tends to be a lot of overlap between them anyways.
Jpop is a pretty broad term, which means it can actually encompass a lot of genres outside of just "pop that is Japanese". It can cover idol groups similar to Kpop (like Perfume and AKB48), electro-type music, 70s/80s pop, and a whole buch of other stuff.
Some Jpop artists regularly collaborate with vocaloid artists, and some even make their own vocaloid songs on the side. This leads to a lot of overlap, with vocaloid songs getting popular in Jpop circles or vice versa. Syudou, Ayase, and Yorushika are examples of Jpop artists/groups that also make vocaloid songs.
Jpop and Jrock are closely related, and as I mentioned earlier, they tend to overlap a lot. A large majority of the songs I listen to tend to fall under "both". It can be pretty hard to make the distinction sometimes.
Some songs and artists stand out as my absolute all time favorites, but I don't want to ignore other artists that I love! Therefore, my all-time favorites are at the bottom, while others I like and think are interesting have a spot on the sidebars ^^