Respectfully; a closing used in military correspondence. /r is used when a superior is addressing a junior, v/r (very respectfully) is used when a junior is addressing a senior, or between peers.
Ensign Schmuckatelli, I know I tasked you with something inane and pointless, have you finished it yet?
r/ means Reddit/ but it can be seen on other platforms such as Youtube, Twitter, Instagram etc. etc. and people say r/woooosh or r/foundthemobileuser or even r/cursedcomments it goes on and on and on it never stops the possibilities are actually endless. It is very interesting to think about and I think it is great!
Jack: Emily what is the name of the subreddit that posts memes?