Yonkoma
A little bit about yonkoma.
Yonkoma manga (”four cell manga”), or 4-koma for short, is a Japanese comic strip format which consist of gags within four cells. The cells are usually equal in shape and flow in vertical sequence. Strips may appear in manga magazines, in graphic novels, or in the comics section of newspapers. Plot often ends within the four cells, although some development may pass on to the next installment. A 4-koma may take up as much space as the entire vertical length of a page, or it may take up the whole page by having the third and fourth cells appear in a new column to the left, depending on the size of the paper.
Well-known manga/anime that started off as 4-koma include: Sazae-san, Azumanga Daioh.
Online, the 4-koma style is used in several webcomics, such as Ghastly’s Ghastly Comic and Sexy Losers. In 2000, Megatokyo introduced a modified 4-koma down as a square instead of completely vertical. This style was adopted by several other comics, including Okashina Okashi and Something Positive. This modified style is still referred to as 4-koma, despite the slight layout difference between it and the original style.
Source: Wikipedia
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