"Since the 20th century, katakana have been used mainly to write non-Chinese loan words, onomatopoeic words, foreign names, in telegrams and for emphasis."(Omniglot.com)
Clearly, the uses for Katakana today are far more numerous than they were 1000 years ago. The first example below, however, is perhaps as close to the original concept of Katakana as pronunciation aid as is still used.
The image above is taken from an issue of the manga, Naruto. Seen in several examples on the above page are Katakana characters used for onomatopoeia. This is similar to the origin of Katakana in that the artist of the manga uses Katakana to represent sounds that one might not otherwise know how to pronounce. Also in this example are Katakana as mimetic words. This differs from onomatopoeia slightly, in that mimetic words tend to emphasize motion as opposed to sound. An example of onomatopoeia above would be ワン in the final frame, whereas in the second system, ズオオオオis an example of a mimetic word.
The second example below is by far the most common usage of Katakana today. Katakana is most often used to transcribe words from other languages. These "loan words" do not derive from Japanese, and often contain sounds that would not otherwise exist in the Japanese language.
The menu comes from a Japanese pizza restaurant. Pizza, obviously not being Japanese in origin is written in Katakana, but so too are many of the other words on the menu. While some of these are obvious, for example ミックスーａ, or mix-a, others represent a more interesting trend in Japanese language. Often a word will be translated into a loan word even when the word exists in Japanese. In this case for instance, the Japanese word for egg: たまご is replaced in the ham and egg pizza (yuck!) with the English loan word Eggusu: ハム＆エッグス.
The final example is far less clear cut than these other examples, and represents Katakana's flexibility.
This image has many examples of Katakana. Some of them are more familiar, but the interesting example is the word ニッポン seen towards the bottom of the image. Nippon is a Japanese word, not a foreign loan word, and it is clearly not an example of onomatopoeia or any of the other common Katakana usages. It can therefore be assumed that Katakana in this case is used for emphasis. Perhaps the advertisement wishes to emphasize this word in order to appeal to a sense of nationhood, or perhaps it is simply to draw the eye to some more important key words in that part of the advertisement.
The point is that Katakana usage varies tremendously. Besides many prescribed usages, the flexibility to use it for emphasis means that Katakana may appear at any given moment in Japanese, and is an important part of Japanese writing and culture.
Sources:
http://www.omniglot.com/writing/japanese_katakana.htm
http://www.merriam-webster.com
http://en.wikipedia.org/wiki/Katakana
http://en.wikipedia.org/wiki/Manga
The second example below is by far the most common usage of Katakana today. Katakana is most often used to transcribe words from other languages. These "loan words" do not derive from Japanese, and often contain sounds that would not otherwise exist in the Japanese language.
The menu comes from a Japanese pizza restaurant. Pizza, obviously not being Japanese in origin is written in Katakana, but so too are many of the other words on the menu. While some of these are obvious, for example ミックスーａ, or mix-a, others represent a more interesting trend in Japanese language. Often a word will be translated into a loan word even when the word exists in Japanese. In this case for instance, the Japanese word for egg: たまご is replaced in the ham and egg pizza (yuck!) with the English loan word Eggusu: ハム＆エッグス.
The final example is far less clear cut than these other examples, and represents Katakana's flexibility.
This image has many examples of Katakana. Some of them are more familiar, but the interesting example is the word ニッポン seen towards the bottom of the image. Nippon is a Japanese word, not a foreign loan word, and it is clearly not an example of onomatopoeia or any of the other common Katakana usages. It can therefore be assumed that Katakana in this case is used for emphasis. Perhaps the advertisement wishes to emphasize this word in order to appeal to a sense of nationhood, or perhaps it is simply to draw the eye to some more important key words in that part of the advertisement.
The point is that Katakana usage varies tremendously. Besides many prescribed usages, the flexibility to use it for emphasis means that Katakana may appear at any given moment in Japanese, and is an important part of Japanese writing and culture.
Sources:
http://www.omniglot.com/writing/japanese_katakana.htm
http://www.merriam-webster.com
http://en.wikipedia.org/wiki/Katakana
http://en.wikipedia.org/wiki/Manga
