Ketchup or Catchup?

Both are correct, depending on your part of the world (and it can also be spelt 'catsup'). In England 'ketchup' is the most often used spelling. In the US, I believe, 'catsup' or 'catchup' is preferred. Although it is now only used meaning a sauce made from tomatoes and vinegar, it earlier referred to any kind of spicy sauce. It seems likely that the word came into English either from the Chinese or from Arabic (possibly ultimately as a borrowed Chinese word). Wikipedia has: http://en.wikipedia.org/wiki/Ketchup

You spell it Ketchup it is a funny thing how both sound the same though huh?L.O.L;]

Both are acceptable. One of the very few words that have two or more acceptable spelling. You may use whatever you are more comfortable with! Cheers!

Ha Ha Ha!!! it's Ketchup! Now you know? not Catchup, you say it in a slang way, you think it's correct. KETCHUP, KETCHUP, KETCHUP.... before going to bed spell it correctly.