「出る」 would be the more natural verb to use than 「ある」.

Some people do write it in kanji even though close to none actually like the kanji because of the "bug" radical.

Yes, I was quite shocked. I don't know if I've ever seen it in kanji (or, at the least, recognized it when I saw it). Apparently it has something to do with ancient Chinese beliefs about a rainbow or something.

When I read it here, I thought it was 蛙 by mistake and was about to ask OP how he got a frog out of a rainbow.

Thank you very much =D I'll keep that in mind (writing rainbow as just にじ) ;pinkbow:

Hi, I would like to know what is the difference between "うまい" and　"おいしい"?

Same meaning. The latter is politer than the former.

Only until about 15-20 years ago, women had rarely used the former. Now they use it rather freely when speaking to close friends.

I assume that men use "うまい" very often as well?

For adult males, definitely.

But if a young boy used it too often at home, his mom might try to correct him. (Talking from my own experience... :) )

Thanks, masaegu.

Ummm... I just want to make something clear.

Difference between ある / いる and です is that ある / いる define an object of having an existence or is in a location while です describes qualities? So, would this be right?

ここは傘です。 (The umbrella has the quality of being here)
ここが傘あります。 (The umbrella exists here)

Your theory was correct, but your execution was not.
The first says "this place is the umbrella" (or, more literally, "as for this place, it is an umbrella") so if you are one inch tall and you find yourself in a huge basin "miles" across, you might realize it's an umbrella and say ここはかさだ！
The second says something like "this is umbrella at the"

これは傘です。 = This is an umbrella.
傘はここにあります。 = The umbrella is (exists) here.