Development of CJK Fonts Source Han Sans and Source Han Serif
Have you ever experienced seeing a box shape or an X mark instead of characters when using fonts? This indicates that the characters are not included in the font. This shape, resembling tofu, is why it's sometimes called "tofu." "Noto," short for "no tofu," is Google's ambitious open-source font collection aimed at eliminating these boxes. Currently, Noto fonts can display over 1,000 languages and more than 150 scripts. 
The Beginning of Source Han Sans and Source Han Serif Development
Adobe in the United States has been considering the development of Pan-CJK fonts (integrated fonts for Chinese, Japanese, and Korean) since 1984. There was an alignment between Adobe's need for funding for integrated CJK font creation and Google's need for Noto CJK fonts. As a result, they collaborated on the development of the Noto CJK font together. Despite the somewhat complex development background, the font is known by different names: Google refers to it as Noto Sans/Serif + character name, Adobe as Source Han Sans/Serif + character name, and in Korea, it's called Source Han Sans/Source Han Serif.
Collaboration with People from Various Countries
The Noto font is the result of collaboration among experts in each character's design. In the case of Source Han Sans and Source Han Serif, the project was overseen and supported technically. The design of Latin/Greek/Cyrillic characters was done by Adobe's U.S. team, while Korean characters were designed by Sandoll. The Japanese and Chinese characters were primarily developed by Adobe's Japan team. Iwata Corporation in Japan and Changzhou SinoType in China also collaborated during the development of Japanese and Chinese characters. Arphic Technology in Taiwan also participated in the creation of Hong Kong characters added from the second version (Version 2.000) onwards.
Source Han Sans was prepared in earnest by Sandoll from December 2012 and released the first version in July 2014. Source Han Serif was prepared in earnest from July 2014 and released the first version in April 2017. During this period, people involved in the project met directly or exchanged emails to progress the project. They also received feedback from employees of various companies, including Google.
Design Characteristics
When designing Source Han Sans and Source Han Serif, attention was paid to their purpose and harmony with other characters. Both fonts were designed for use in body text and suitable for both print and mobile device screens. The production method involved creating samples of Latin, Chinese characters, and Kana first, and then designing Korean characters to match them.
For Source Han Sans Korean characters, the following design considerations were taken into account:
- The character width was narrowed to accommodate more characters in small mobile environments.
- To save space, the tops of 'ㅎ' and 'ㅊ' were positioned vertically, and the consonants and vowels were designed to be as close as possible to reduce unnecessary space.
Roman, Chinese characters, and Kana in Source Han Sans have large inner spaces and simple strokes. Roman characters also capture hand movements, such as treating the stroke ends of characters like 'c' and 's' diagonally.
To achieve harmony, the following designs were applied to Korean characters
- They were designed to be concise, for example, the vertical stroke of 'ㅍ' was made straight to attach to the horizontal strokes above and below.
- To emulate hand movements, the beginnings and endings of horizontal strokes connecting consonants and vowels like 'ㅢ, ㅚ, ㅘ, ㅟ, ㅝ, ㅞ, ㅙ' were all treated diagonally.
For Source Han Serif Korean characters, the following design considerations were taken into account:
- Serifs and endings were reduced in size and simplified to avoid being visually overwhelming and to provide a clean overall impression.
- Strokes were thickened, especially in light weights, and the contrast between vertical and horizontal strokes was reduced to prevent strokes or horizontal lines from appearing thin at small sizes.
Source Han Serif Roman, Chinese characters, and Kana are positioned between classic and modern styles, with many characteristics refined to reflect the writing tool's influence, such as pens or brushes. Roman characters have a strong sense of both vertical and horizontal lines.
To achieve harmony, the following designs were applied to Korean characters: 
Stroke shapes were simplified and refined without becoming overly simplified or mechanical.
To give a modern feel, letter forms and inner spaces were slightly larger, the top of 'ㅇ' was removed, and the vertical stroke of 'ㅍ' was made into a stroke rather than a dot for a concise shape.
The slope of the horizontal strokes was made closer to horizontal.
Additionally, when designing Source Han Serif Korean characters, the contrast between horizontal and vertical strokes was not as pronounced as in Roman and Chinese characters, and the style leaned towards handwriting, closer to a semi-cursive script. This decision was made to apply the unique characteristics of Korean Mingjo style, respecting the development history, culture, and preferences of each character's design rather than forcing them to match each other.
Ancient Korean and Korean Sentence Punctuation
In addition to modern Korean 11,172 characters, Source Han Sans and Source Han Serif also include 500 complete forms of ancient Korean and 1,488 combinational jamo characters. With combinational representation, you can input over a million characters of ancient Korean without limitation. Since there was almost no experience in creating ancient Korean, a lot of effort was put into reading related books and directly consulting authors.
Sentence punctuation for East Asian characters often doesn't match well in size and position when written like Roman characters. Therefore, several sentence punctuations were separately created to fit each character. Korean sentence punctuations have the same shapes as Roman punctuation but are adjusted in size and position to fit Korean characters. The spacing width is also different between Roman and Korean punctuation. Korean sentence punctuation can be used by changing the language of Adobe InDesign's character panel to Korean.
Source Han Sans and Source Han Serif continue to be updated after the first release based on feedback from users, including adding Hong Kong characters, modifying shapes and designs, and releasing variable fonts. You can find several versions of the font released so far at the following links (Source Han Sans/Source Han Serif).
Development of CJK Fonts Source Han Sans and Source Han Serif
Have you ever experienced seeing a box shape or an X mark instead of characters when using fonts? This indicates that the characters are not included in the font. This shape, resembling tofu, is why it's sometimes called "tofu." "Noto," short for "no tofu," is Google's ambitious open-source font collection aimed at eliminating these boxes. Currently, Noto fonts can display over 1,000 languages and more than 150 scripts.
The Beginning of Source Han Sans and Source Han Serif Development
Adobe in the United States has been considering the development of Pan-CJK fonts (integrated fonts for Chinese, Japanese, and Korean) since 1984. There was an alignment between Adobe's need for funding for integrated CJK font creation and Google's need for Noto CJK fonts. As a result, they collaborated on the development of the Noto CJK font together. Despite the somewhat complex development background, the font is known by different names: Google refers to it as Noto Sans/Serif + character name, Adobe as Source Han Sans/Serif + character name, and in Korea, it's called Source Han Sans/Source Han Serif.
Collaboration with People from Various Countries
The Noto font is the result of collaboration among experts in each character's design. In the case of Source Han Sans and Source Han Serif, the project was overseen and supported technically. The design of Latin/Greek/Cyrillic characters was done by Adobe's U.S. team, while Korean characters were designed by Sandoll. The Japanese and Chinese characters were primarily developed by Adobe's Japan team. Iwata Corporation in Japan and Changzhou SinoType in China also collaborated during the development of Japanese and Chinese characters. Arphic Technology in Taiwan also participated in the creation of Hong Kong characters added from the second version (Version 2.000) onwards.
Source Han Sans was prepared in earnest by Sandoll from December 2012 and released the first version in July 2014. Source Han Serif was prepared in earnest from July 2014 and released the first version in April 2017. During this period, people involved in the project met directly or exchanged emails to progress the project. They also received feedback from employees of various companies, including Google.
Design Characteristics
When designing Source Han Sans and Source Han Serif, attention was paid to their purpose and harmony with other characters. Both fonts were designed for use in body text and suitable for both print and mobile device screens. The production method involved creating samples of Latin, Chinese characters, and Kana first, and then designing Korean characters to match them.
For Source Han Sans Korean characters, the following design considerations were taken into account:
Roman, Chinese characters, and Kana in Source Han Sans have large inner spaces and simple strokes. Roman characters also capture hand movements, such as treating the stroke ends of characters like 'c' and 's' diagonally.
To achieve harmony, the following designs were applied to Korean characters
For Source Han Serif Korean characters, the following design considerations were taken into account:
Source Han Serif Roman, Chinese characters, and Kana are positioned between classic and modern styles, with many characteristics refined to reflect the writing tool's influence, such as pens or brushes. Roman characters have a strong sense of both vertical and horizontal lines.
To achieve harmony, the following designs were applied to Korean characters:
Stroke shapes were simplified and refined without becoming overly simplified or mechanical.
To give a modern feel, letter forms and inner spaces were slightly larger, the top of 'ㅇ' was removed, and the vertical stroke of 'ㅍ' was made into a stroke rather than a dot for a concise shape.
The slope of the horizontal strokes was made closer to horizontal.
Additionally, when designing Source Han Serif Korean characters, the contrast between horizontal and vertical strokes was not as pronounced as in Roman and Chinese characters, and the style leaned towards handwriting, closer to a semi-cursive script. This decision was made to apply the unique characteristics of Korean Mingjo style, respecting the development history, culture, and preferences of each character's design rather than forcing them to match each other.
Ancient Korean and Korean Sentence Punctuation
In addition to modern Korean 11,172 characters, Source Han Sans and Source Han Serif also include 500 complete forms of ancient Korean and 1,488 combinational jamo characters. With combinational representation, you can input over a million characters of ancient Korean without limitation. Since there was almost no experience in creating ancient Korean, a lot of effort was put into reading related books and directly consulting authors.
Sentence punctuation for East Asian characters often doesn't match well in size and position when written like Roman characters. Therefore, several sentence punctuations were separately created to fit each character. Korean sentence punctuations have the same shapes as Roman punctuation but are adjusted in size and position to fit Korean characters. The spacing width is also different between Roman and Korean punctuation. Korean sentence punctuation can be used by changing the language of Adobe InDesign's character panel to Korean.
Source Han Sans and Source Han Serif continue to be updated after the first release based on feedback from users, including adding Hong Kong characters, modifying shapes and designs, and releasing variable fonts. You can find several versions of the font released so far at the following links (Source Han Sans/Source Han Serif).