Finally figuring out flickr

Ive had a flickr account for a while now. I go through long periods where i do not use it, occassionaly i get an email about a contact or something so i check in. Well i was just having alook and when i signed in to my account it said  new comments, so i had a look and the comments were left eight days ago and i didnt get an email. I ventured of into the settings and was surprised to see lots of options i have never seen before.

Can anybody tel me what  “Your blog upload email ” means? I think i can work out the others but not sure how to use this one. So as i said im finally figuring it out after having it for about 18 months.