In sanskrit, it is karm NOT karma.Ram NOT RamaYog not Yoga.Why do people put the extra "a"??

where is the curry?!

You are forgetting the : , this nasal is after every noun, be it Yog, Karm or Ram. In Hindi, the : is not used so much and thus we get the impression that the west adds an 'a' to show off.Strictly speaking, they should be Yogah, Karmah, Ramah to preserve the actual sound of :

americans, or whoever like to put the extra flare around our words. makes spelling hard.

its easier to pronounce that way for non-Indians.

Because although the stem is "Yog-", etc, in the nominative singular for a-stem nouns, an "-ah" suffix is added, so karm becomes karmah, and is the form of the noun more commonly imported into English.

Good question. If you learn basic Sanskrit you will know the answer. When Sanskrit words were being transliterated into English in the earlier days the completion of the consonant sound was shown by adding an 'a'. The extra 'a' acts as a medium to complete the consonant sound. Without it, pronounciation would end in a half or 'halanta' as we call it in sanskrit. Example of the halanta would be like in the word 'kyon' in Hindi where the consonant 'ka' is halfed. Unfortunately, there does not exist any medium that I am aware of to make regular English speakers aware of the the first vowel of the devanagari alphabet, viz., 'a'. The second one is 'aa'. Today, even in Hindi the consonant sound is not completed for any word and hence people cannot make out the purpose of the extra a. So even in Hindi 'karma', 'Rama', 'Yoga' are not pronounced the proper way. This leads to people reading the extra added 'a' as 'aa',i.e., the second vowel which corrupts the pronounciation. This also leads to the mistaken assumption that the a represents the last vowel 'ah' of the devanagari alphabet. (An answerer above me has made the same mistake)So the case we have here is that the sanskrit pronounciation is corrupted with or without the extra 'a'. An A class problem if ever there was one.

I would think it is to make the word an english word... lots of words have roots from other languages... but they aren't an exact translation. Why should these words be any different?