TLDR - An Idol is a hired performer whose most marketable skill is their cuteness. Idol's have their own Culture and Aesthetic. Idols also have a business model centered around providing merchandise to obsessive fans.

Idols are a concept that, as we know it, started in the late 1960s in Japan. In short, Idols are manufactured starlets that are marketed to sell music and products mostly because of how they look, or who they are (this can be directly contrasted with the singer-songwriter). In general, an Idol must embody cuteness and will be required to sing, dance, and speak. Generally an Idol is only skilled in one of these areas (besides cuteness which is mandatory). In the current Idol Warring Period, most Idols are not skilled enough in any of the three main areas to be considered a professional, although there are some exceptions. Being an Idol is an Aesthetic, being an Idol is an identity, being an Idol is a vibe. The Idol Aesthetic usually involves traditionally feminine “Western” inspired costumes (ie. cheerleaders, ballerinas, European dolls, etc…) that are color coded. The Aesthetic also usually involves traditionally feminine accessories and garments like: dresses; skirts; ribbon; lace; tulle; stockings; etc… The Aesthetic usually exposes a lot of leg (thigh or higher). Lastly, the Idol Aesthetic takes Japan's Kawaii obsessed culture and turns it up to 10. Idols are OBSESSED with being cute, its their job, its their profession. Idols will certainly be the cutest people in the music industry, even if they can not sing a lick. Here are some examples of the Idol Aesthetic.

Idol's performance is normally just slightly above a normal person's capacity. Most Idol dance routines can be learned by anyone. Most Idol songs can be sung in karaoke by just about anyone. This feeds into the idea that “I can be an idol if I want to,” because the bar for entry as an idol is much lower than for a professional.

The Japanese Idol is also separate and distinct from other idols such as Korean-pop Idols or Chinese-Pop Idols, who themselves have separate and distinct cultures, histories, and aesthetics. In America, we have no direct comparisons to Idols in our music industry, the closest we have is boy bands and girl groups (see New Edition, Backstreet Boys, TLC, and Destiny's child). This page and Aidoru Hands Music Company is focusing on the traditions and culture of the Japanese Idol.

I think the best place for anyone to start is learning about Idols is the Wikipedia page (Look here for English, and look here for Japanese).

The next best place is to have a look at TV Trope's article on the topic.

Idols are mostly young (under 21) female entertainers who have above average looks. They traditionally have a focus on feminine looking women and have lyrics that cater to adult men. They traditionally are contracted with to sell a musical product, as opposed to creating a musical product. The type of music they perform to is largely irrelevant, but it tends to be apolitical, feel-good, pop styled music of whatever era they are in. If a performer who identifies as an idol sings a song, that song is considered Idol Song. Idol Song is not really a genre of music, but more of a collection of ideas or aesthetics.

I am not a historian nor a musicologist. My interest in Idols is solely from a fan standpoint. So my knowledge of Idols is derived directly from my research on the things I like. But I have enough knowledge to paint in broad strokes concerning the general history of Idol Culture and Idol Song as a genre.

The Japanese have a fantastic knack for absorbing other's culture and giving it a Japanese twist that is unique and distinct (think curry, fashion, or video games). Idols, as the concept the Japanese would take, started in France. In Japan, the aesthetic was crystallized by Sylvie Vartan in the film Cherchez l'idole.

However, this aesthetic and type of “cuteness over talent” marketing style was born out of the Yé-yé-Girls movement of France in the 1960's. I think Serge Gainsbourg had a strong influence on how the Japanese started marketing their Japanese Idols. Gainsbourg sexualized the ladies he wrote for, he focused on them seeming innocent, and almost exclusively (from what I can tell) wrote lyrics from the perspective of the “Male Gaze.” I think this was a strong pull for Japanese Executives who thought this would be a great way to sell records. Contrast a Gainsbourg song with a song that Yamaguchi Momoe became popular by.

France Gall's 1966 single Lollipops (written by Serge Gainsbourg)

Notice that in the video for the song Lolipops that there are many phallic shapped loliipops being put in the France's mouth. This unfortunate imagery is made worse by the fact that the 18 year old did not understand that the song was implying oral sex.

Yamaguchi Momoe's 1973 single Unripe Fruit

You can contrast that France Gall song with this Momoe Yamaguchi song where the 14 year old sings that “If you wish it, You can do anything you want with me, you can tell that I'm a bad girl.” In fact a part of Momoe Yamaguchis initial popularity was due to her as an adolescent girl singing songs with suggestive lyrics.

Despite Japanese Idols being inspired by Ye-Ye-Girls, very soon they became their own thing. The period between 1980 and the pop of the economic bubble Idols experienced a golden era where a lot of what we now think of as Japanese Idol Culture was crystallized. If we look at an Idol from the 80's in Japan like Nakamori Akina we can see a lot of aspects of contemporary Idol Culture. Lets look at this performance of Shoujou A.

We can see:
Above Average Attractiveness
Youthful Appearance
Natural Make up
European inspired fashion (as opposed to how they may dress in enka or kabuki)
Feminine accessories like gloves, dresses, skirts, heels, bows, tulle, lace, and ribbon
Dance Routines (which mostly are absent in other forms of popular music in Japan at the time)
Lyrics about love or innocence
Visually modest, but planned displays of sexuality (via lyrics or costuming)
Theses are just some of the many things we attribute to the Idol Aesthetic.

If we look at this Seiko Matsuda single from the 80's we can hear how fan culture was starting to coalesce.

We can hear fans engaging in fan chants. But fans of this era also did other things like blow whistles and cheer for the idols they support, just like they were sports athletes. All these aspects are carried through up until now and have evolved to meet the times.

The Idol Warring Period is a Japanese joke in which people describe the current idol period (after the pop of the bubble) like the Sengoku period of Japan where there was a lot of war and civil upheaval from 1467 to 1615. This is opposed to the golden era of idols in the 1980's (before the pop of the bubble) where it seemed the like the profits would never end, the competition was never too crowded, and every consumer had enough disposable income to support the incredibly expensive “Idol” style of entertainment.

This Idol Warring Period has been fueled by many things including: the internet giving a platform to those outside of the industry proper; the cost of music production going down; and the general popularity of idols inspiring more and more people to aspire to being an idol. All of this is under-pinned by the flavor of sexism in Japan, which makes it very difficult for Japanese Women to be accepted in any role that does not enforce gender normative activities. In addition, being an idol is a great way for a cute girl to earn some money and not ruffle any feathers (see women's work in Japan,lgbt in Japan, and Takarazuka Revue). Before the 2000's, the only way to become an idol was to go through some sort of industry vetting process (audition, A&R rep, etc…). This had the effect of making it much more difficult to debut as an idol unless you went through the machine. But Idols start graduating from Actor's schools (like in speed in Okinawa and Perfume in hiroshima in large numbers, and net idols become a thing, but most importantly is the birth of local idols. When we start having local idols perform and girls see idols more consistently, more and more girls want to become idols. At this point we can devolve into a whole other number of topics that accompany local and underground idols, but we must save that conversation for another day. The long and short of it is, a sizable amount of the girls participating in the National idol groups, were local idols first. Idols proliferated the scene and became truly a part of Japanese culture. Bigger organizations like Hello!Project, Johnny's Entertainment, or AKB48 even have their own feeder groups that accept young trainees who pay for lessons in hopes of becoming good enough to join the bigger organizations.

Before the Idol Warring Period, Idols were generally either solo (like Matsuda Seiko) or duos (like Pink Lady). However, during the golden era the first successful large idol group was started called Onyako Club. They would start the newer marketing tactic of having a large number of idols to sing the songs so that there was a higher chance to attract fans with more variety in more cute girls. In our current era, there are few solo idols (an Idol Performing by themselves) in the mainstream, most idol group have at least 3 people. So in the Idol Warring Period, there are almost exclusively Idol Groups, thanks to the success of Onyaku Club. By the way, the Idol Culture almost completely crashed in he 90s after the bubble popped. It was the Idol Group Morning Musume that brought idols back. The producer for Morning Musume says that he was inspired by Onyaku Club when creating Morning Musume. The success of Morning Musume served as a catalyst for the Idol Warring Period.

There is so much diversity with the current Idol Warring Period that there is something for everyone. There are slim idols, fat idols, black idols, white idols, nerd idols, goth idols, real idols, pixelated idols, old idols, young idols, cute idols, cool idols, literally whatever itch you want to scratch, an idol is waiting to do it. Here are some examples of Idols.

Additional Reading

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