Cangjie input method
The Cangjie input method (倉頡輸入法) is a shape-based system for entering Chinese characters into computers and other digital devices using a standard QWERTY keyboard, by decomposing characters into up to 24 basic graphical components or radicals mapped to specific letters.[1] Invented between 1972 and 1978 by Taiwanese computer scientist Chu Bong-Foo (朱邦復), it is named after Cangjie, the legendary figure in Chinese mythology credited with creating the Chinese writing system.[2] Developed initially for typesetting and publishing purposes in Taiwan during the 1970s, the method was released into the public domain in 1982, allowing widespread adoption without licensing restrictions.[1] The system's structure divides the 24 key components into four philosophical categories—natural elements (A-G), stroke types (H-N), human-related forms (O-R), and abstract shapes (S-Y)—excluding Z and using X for special cases, enabling users to input characters by analyzing their construction from left to right, top to bottom, or outside to inside.[3] Complex characters are encoded with a maximum of five letters, following rules for one-unit (up to four components), two-unit (two plus three), or three-unit (two plus two plus one) breakdowns, with abbreviations for efficiency.[3] Unlike phonetic methods such as pinyin, Cangjie relies on visual decomposition rather than pronunciation, making it particularly suitable for traditional Chinese characters and reducing ambiguities in homophones, though it requires users to memorize component codes.[2] Widely implemented in operating systems like macOS, Windows, and various mobile platforms, Cangjie remains a standard input method in regions using traditional Chinese, especially Hong Kong and Macau, where it supports efficient typing for over 70,000 characters without needing phonetic transcription.[2] Variants such as Easy Cangjie simplify codes to two letters for common characters, enhancing accessibility for beginners while preserving the core shape-based logic.[3] Its enduring impact lies in pioneering non-phonetic Chinese computing, influencing subsequent input technologies and facilitating the digital preservation of Chinese script in professional and educational contexts.[1]Overview and Fundamentals
Keyboard Layout
The Cangjie input method employs a modified standard QWERTY keyboard layout, utilizing 24 of the 26 alphabetic keys (A–Y, excluding X and Z) to represent basic radicals derived from common graphical components of Chinese characters. This design, created by Chu Bong-Foo during 1972–1978 and released into the public domain in 1982, prioritizes logical grouping for ease of learning and efficient typing on existing hardware without specialized peripherals.[1][4] The keys are organized into four conceptual groups, each associated with thematic categories that reflect structural and philosophical aspects of Chinese writing, enhancing ergonomic access by clustering related shapes—such as those mimicking basic strokes—for sequential input. The first group (A–G) covers elemental and celestial forms; the second (H–N) focuses on fundamental stroke types like horizontals, verticals, dots, and hooks; the third (O–R) denotes body-related components; and the fourth (S–Y) addresses geometric shapes and enclosures.[1][3]| Group | Keys | Representative Radicals and Descriptions |
|---|---|---|
| Philosophical/Elemental | A–G | A: 日 (rì, sun); B: 月 (yuè, moon); C: 金 (jīn, metal); D: 木 (mù, wood); E: 水 (shuǐ, water); F: 火 (huǒ, fire); G: 土 (tǔ, earth). These evoke natural and cosmological motifs.[3] |
| Strokes | H–N | H: 竹 (zhú, bamboo head, slanting strokes); I: 戈 (gē, halberd, dot); J: 十 (shí, cross); K: 大 (dà, enclosing form); L: 中 (zhōng, verticals and center); M: 一 (yī, horizontals); N: 弓 (gōng, curved/hooked lines). This cluster facilitates input of primary stroke categories like horizontal, vertical, dot, and angular for ergonomic flow.[5][3] |
| Body-Related | O–R | O: 人 (rén, person); P: 心 (xīn, heart); Q: 手 (shǒu, hand); R: 口 (kǒu, mouth). These map to anthropomorphic elements commonly found in character structures.[3] |
| Shapes/Transformational | S–Y | S: 尸 (shī, corpse, lid); T: 廿 (niàn, twenty, crossed verticals); U: 山 (shān, mountain); V: 女 (nǚ, woman); W: 田 (tián, field, enclosure); Y: 卜 (bǔ, divination, lines). These handle enclosing and positional forms.[3] |
Keys and Radicals
The Cangjie input method utilizes 24 primary radicals, referred to as "letters" or "basic shapes" (字根), which form the core building blocks for analyzing and inputting Chinese characters by their structural components rather than pronunciation or traditional Kangxi radicals. These radicals are assigned to the alphabetic keys A–Y on a QWERTY keyboard (excluding X and Z), with each representing a distinct visual pattern derived from common elements in character formation, such as strokes, enclosures, or symbolic motifs. Phonetically, the radicals are often named after familiar characters (e.g., 日 for "rì," meaning sun), while visually they encompass simplified glyphs like 丨 (vertical stroke) or ㄥ (enclosure). This design allows users to break down characters into up to five radicals for encoding, emphasizing geometric logic over rote memorization.[3] The radicals are categorized into four thematic groups to facilitate learning and recall: the philosophical group (A–G), stroke group (H–N), body parts group (O–R), and shapes group (S, T, U, V, W, Y). The philosophical group draws from natural and elemental concepts, including 日 (A, sun, representing left or upper enclosures), 月 (B, moon, for covers or lying forms), 金 (C, metal, for spreading or knife-like shapes), 木 (D, wood, for tree-like branches), 水 (E, water, three dots or flowing lines), 火 (F, fire, four dots or flames), and 土 (G, earth, squares or grounds). The stroke group focuses on fundamental calligraphy elements, such as 竹 (H, bamboo, slanting strokes), 戈 (I, halberd, dots or tents), 十 (J, cross, intersecting lines), 大 (K, great, forked or curved forms), 中 (L, middle, vertical strokes), 一 (M, one, horizontal strokes), and 弓 (N, bow, hooks or bends). The body parts group includes 人 (O, person, standing figures), 心 (P, heart, seated or inner forms), 手 (Q, hand, crossed or claw shapes), and 口 (R, mouth, openings or boxes). The shapes group covers 尸 (S, corpse, lids or boxes), 廿 (T, twenty, doubled horizontals), 山 (U, mountain, peaks or sprouts), 女 (V, woman, crosses or skirts), 田 (W, field, grids or frames), and 卜 (Y, oracle, divining rods or verticals). Although some sources suggest alignments with five basic stroke types (horizontal, vertical, dot, left-falling, right-falling), the official groupings emphasize these broader categories for structural representation.[7]| Key | Radical Symbol | Phonetic Name | Visual Description | Group |
|---|---|---|---|---|
| A | 日 | Rì (sun) | Left/upper enclosure, rectangular form | Philosophical |
| B | 月 | Yuè (moon) | Cover, lying supine, flesh-like | Philosophical |
| C | 金 | Jīn (metal) | Spreading, knife, enclosing sides | Philosophical |
| D | 木 | Mù (wood) | Tree, branches, crossed trunks | Philosophical |
| E | 水 | Shuǐ (water) | Flowing lines, three dots | Philosophical |
| F | 火 | Huǒ (fire) | Flames, four dots | Philosophical |
| G | 土 | Tǔ (earth) | Ground, square, drop | Philosophical |
| H | 竹 | Zhú (bamboo) | Slant, left-falling stroke | Stroke |
| I | 戈 | Gē (halberd) | Dot, tent, weapon form | Stroke |
| J | 十 | Shí (ten) | Cross, intersect | Stroke |
| K | 大 | Dà (great) | Fork, curve, person with arms | Stroke |
| L | 中 | Zhōng (middle) | Vertical stroke, line through | Stroke |
| M | 一 | Yī (one) | Horizontal stroke, top/bottom line | Stroke |
| N | 弓 | Gōng (bow) | Hook, bend, arc | Stroke |
| O | 人 | Rén (person) | Standing figure, slant cross | Body Parts |
| P | 心 | Xīn (heart) | Seated, inner chamber | Body Parts |
| Q | 手 | Shǒu (hand) | Claw, double cross, hook | Body Parts |
| R | 口 | Kǒu (mouth) | Opening, square enclosure | Body Parts |
| S | 尸 | Shī (corpse) | Lid, box, slanting roof | Shapes |
| T | 廿 | Niàn (twenty) | Doubled horizontal, grass head | Shapes |
| U | 山 | Shān (mountain) | Peak, sprout, angled lines | Shapes |
| V | 女 | Nǚ (woman) | Cross, skirt, even fields | Shapes |
| W | 田 | Tián (field) | Grid, frame, well | Shapes |
| Y | 卜 | Bǔ (divine) | Divining rod, vertical probe | Shapes |