Story manga
Story manga (Japanese: ストーリー漫画) is the dominant form of comic in Japan whose theme are overtly dramatic (akin to film, hence the name "story" manga) which utilise time synchronized sequence, size and layout of strips in a double-page spread with viewing speed of the reader to simulate dynamism, similar to cinema storyboards. The time-control technique of Story Manga means that frames are set out chronologically, linked by motion lines or onomatopoeia with little or no narrative text. It is generally accepted that Osamu Tezuka founded/pioneered story manga after WWII, while recent research suggest that technique of cinematic presentation has been used much earlier than WWII. In contrast, the comics prevalent in America are characterized by more densely drawn color illustration accompanied by a larger amount of text. This type of comic, similar to story book, requires readers to stop at each frame for a significantly longer time and "read". Moreover, majority theme of American comics were limited until very recently to the superhero genre, whereas story magna tend to be more diverse in genre and theme.
Komawari (Framing)
Komawari literally means Frame splitting/allocation. Because Japanese language is written from top to down, right to left, frames can be viewed more easily if they zig zagged from top to down and right to left. This arrangement allowed the reader to view rather than read the page. Also to compensate for the increase viewing speed between frames, Tezuka, who is credited as the founder of story manga, conveyed information more through picture rather than through text. For this purpose, he eliminated narrative text almost entirely by introducing more sequences of strips to convey the shift in events or by using side characters' dialogue to indicate the story. To maximize information through pictures, he utilized many symbols and onomatopoeia, for example, in Japanese manga, "#" symbol on someone's forehead (frown) means that person is cross. As this technique massively increased the number of strips needed to convey each scene of story, caricatured line drawing similar to Disney cartoon became widely popular among Japanese comics.
Origin
Until very recently, the establishment of the time-control system had been credited to the work of Osamu Tezuka in the period immediately following World War II. However, recent academic research show that a prototype version of story manga can be seen in much earlier works such as "Krazy Katt" (although that was still one-panel comic strip) and "Sho-chan no Bouken" (Sho-chan's Adventure), published in 1923 which has 52 frames over 13 pages for each story using cinematic viewing angle such as zoom out or close up. This pre-dates The Adventures of Tintin, first published in 1929, and "Superman" from 1933.
However, it is accepted Tezuka made concerted effort to move manga's story telling from children's fantasy story to more mature cinematic story. He often introducing tragic plot element (such as death of main characters) and characters with complex background and motive. His manga story ranged from medieval themed action horror (Dororo), medical drama (Blackjack) or fantasy historical epic (Hinotori) to modern adaptation of classic literature (Faust). While it is not longer accepted that Tezuka invented cinematic technique, there is still wide consensus that he is the founder of "story (based) manga".
Osamu Tezuka also made number of innovation in cinematic technique, most notable one being much freer and therefore more dynamic use of frame size and layout as well as liberal use of onomatopoeia and symbols to convey information without use of texts.
Influence of Gekiga
Gekiga (劇画?) is Japanese for "dramatic pictures." The term was used by Japanese cartoonists who wanted to differentiate their works from mainstream story manga (manga), which was popularised by Tezuka.
(Story) manga became vastly popular in Japan and became main revenue source of major print publishers in Japan, often surpassing the combined revenue of book and magazine. Many popular manga start to be serialised weekly. As a result of this rapid weekly production cycle, detailed drawing in colour became practical impossibility and Disney like caricatured face in black and white become the main drawing style of manga.
However, by the late 1960s and early 1970s the children who grew up reading manga wanted something aimed at older audiences and gekiga provided for that niche. These "dramatic pictures" emerged not from the mainstream manga publications in Tokyo headed by Osamu Tezuka but from the lending libraries based out of Osaka. While weekly production cycle of manga necessitated Disney like line drawing, the lending library industry allows gekiga cartoonist to spend more time and resource on drawing and writing. As a result, gekiga is characterised with more dense and detailed and realistic drawing and are much more artistic and experimental (and often offensive). They eliminated caricatured drawing and criticised Tezuka's story manga for still containing comedic element aimed at children. The growing popularity of gekiga, in turn, influenced Tezuka and his followers who began to draw gekiga themed cartoon after the 1970s.
As the distinction between manga and gekiga begun to blur, some gekiga artists began to strive for mainstream success. The main bottleneck of gekiga in mainstream production was a highly intensive and time constrained weekly production cycle of shonen-shi. Takao Saito, of Gold 13 fame, is credited as breaking this bottleneck by introducing factory style production method, where each "workers" specialise in one aspect of manga production, such as writing, framing, lining, toning, tracing and backgrounds. Saito Takao event went as far as creating Saito Production Ltd, which manage and directly publish his team's work, and declare that he no longer directly involve himself in drawing. This mode of production has later been adopted universally by all professional cartoonist.
Another consequence of this mode of production is authorship of manga. In Japan, authorship of manga is not given to person who actually draw the picture but instead given to someone who draw up komawari (literally means frame division), that is someone who decide size and positioning of strips for pictures and dialogue, much akin to directors of film. In professional manga production which often have to produce episode every week, majority of drawing are almost always done by numbers of assistants who specialising in separate field such as background, inking/tracing or placing toner.
By the 1980s, as library lending industry shrink and disappear, gekiga become a genre within story manga, and the word manga in Japan, by default, begun to mean story manga. One of the signature gekiga style story manga which became well known globally is Akira. Gekiga now is seen by many as the continuation of movement started by Tezuka, and is incorporated as a style within manga.