Earlier today I started an e-mail with Yep which was then replied to with Yup, this went on with yep and yup starting multiple e-mails. I began to wonder if Yup was more correct or if it was a regional thing, or if someone was poking fun at me. Luckily, Urban Dictionary came to the rescue.
Yep - An absolute yes that implies far more than a simple yes. Alternately, an affirmative response with minimal energy.
When someone tells you that a site going down midday is bad what else can you say? My use was a bit of both.
Yup on the other hand,
is a generic term of agreement issued often by a non-listening party, typically used while performing an additional important task, such as watching tv.
So, given that a previous Yup was used in an e-mail thread in which someone said a server going down in the middle of the day is bad, seems actually to be a correct response while multi-tasking and needing to say something. Yep, I for one feel better.