Why the ou? (Japanese)?

Question

I've noticed that people use o and ou interchangeably in Japanese. For example, Ohayo and ohayou. Why is this? Are they pronounced the same?

Answer 1

about good morning

correct writing is 'o ha yo u' (4 syllables).

ohayo is casual term or slang.

Answer 2

Actually, the o and the ou do make a difference.

Not only are they pronounced slightly different, their meanings differ a bit as well.

For ex:   ohayo     vs     ohayo u

If written in Japanese,     ohayo u would be the proper form, however, so many teenagers speak it fast and sort of like a slang that it was written as ohayo

There are also many other words which fall into this category.

Answer 3

they're  the same, and are pronounced  the same (in  the case of おはようとおはよ)

other words might not be pronounced the same with long vowels,  like

おばあさん obaasan grandma

おばさん obasan aunt

i guess with　おはよ, it's personal preference. :)

hope i helped!

Answer 4

It's just two different ways of writing the same thing. The final "o" in "Ohayo" is actually a long (double) o, and in Japanese phonetics it is considered to consist of "o+u".  In other words, "ou" = "oo" which is sometimes written "o".  Got it?

Answer 5

おはよう＝Ohayou

The last word "Yo" is a bit longer. If you are able to read the hiragana of "good morning" in Japanese. The correct pronunciation is "Ohayou" not "Ohayo". But, both are understandable of course.