Japanese and Oriental ingredients: Rice vinegar

Rice vinegar

The Japanese rice vinegar has a gentle rice flavour with very light natural sweetness, light but stingy and clear sour taste. Basic one has not malted or sweetened. The clear taste of rice vinegar does not bother the food original taste.
Using the same basic rice vinegar, there are so many varieties of way to marinate ingredients; the vinegar is seasoned differently per the marinating ingredients, to suite the ingredients its taste.
For example, the vinegar used for sushi rice is not plane rice vinegar, but the one seasoned by sugar and salt. By the portion of sugar and soy source mixed with vinegar makes the basic few varieties. Mixing with flutes juice like lemon, or flutes meat like ume (salted plum) are the another popular style. 
Marinating food is one of very popular way to preserve food and kill bacteria, which is easier to grow under the Japanese high heat & humidity summer condition.

<Example products you can find in UK>
I have to say, I use only Mizkan brand. I never could accept any other makers taste as this is my family taste. But I think I'm not the only one.

Daily use: Mizkan Distilled White Vinegar

Honestly this type has lesser flavour but really cheaper. Yet the stingy vinegar sour taste gets much gentle than the western distilled white vinegars. For the heated menu like Sweet and Sour pork, this works well.

 Good: Mizkan Rice Vinegar (Most of Japanese grocery store has this product)

Has richer rice flavour, slightly sweeter and lesser stingy sour taste than above. Usually cooked with sugar and other ingredients for a very short period to control the stingy sour taste even more.
ASDA carries equivalent product:

Variety: Mizkan Sushi-zu (Seasoned vinegar/Sushi vinegar)

You can make your own Sushi-zu from above regular rice vinegar, but this is very convenient for daily use.
It has been seasoned by sugar and salt, and has lesser stingy sourness than above.
If you are looking for the rice vinegar for general salad, this is the one you like to buy.
Lately Tesco start to carry the next product:

Variety: Mizkan Powdered Sushi Vinegar Mix

If you are novice making sushi rice, this powder style is easier to make sushi rice evenly.

For cooking
Commonly used for marinating vegetable, fish and sea food. Cooking meat with vinegar softens the meats. The sushi rice vinegar makes very simple and light tasting salad dressing. 

Other use
Lately vinegar is more likely to be used for cleaning household, just like the lemon juice.