When watching Thai Tv, ive noticed that in most conversations , a sentance nearly always ends with some one saying ...Kap or Ka, can some one please explain to me just what this means , ...Thanks.

Men say 'krup'. Women say 'ka'.

Its used in a lot of ways, mostly on the end of a sentence to give what you are saying a polite conotation. 'I don't want to go' could sound rude, while 'I don't want to go krup' will sound polite.

Also it is used as a confirmation word, kind if like 'yes' in English.

In another tone, it can also be used when you didn't catch what was said, kind of like 'what was that'.