I often see, generally in user polls, the original poster requesting that users
“reply +1 to keep the post on top”.
What does this mean, and how would I reply “+1”.
Thanks much!
+1 means you agree with the above post and -1 would mean that you disagree. Sometimes people demonstrate their enthusiasm by posting +10000 or some other large number.
To keep a topic near the top of the recent posts screen then “bump” is most often used.
+1
Okay, I think I know what you mean now. So to reply +1 if I agree, I would just post a
reply with +1 in the message body, as opposed to just clicking the yes button and not
bothering to post a reply at all.
I’ve never used “bump”, but I’m sure I’ll run into it sooner or later.
Thanks much!
+1 optional text 
But, if it’s a Poll then you would also vote, otherwise your vote wouldn’t count. However, you don’t need to post the +1 to vote if you don’t want to in a Poll.