ready-to-hand
「上手状态」（海德格尔术语 Zuhandenheit）：在使用者与工具的熟练关系中，工具退隐到实践背后，使用者专注于手头的活动本身而非工具本身。
English Definition
"A Heideggerian mode of engagement in which a tool or system is so well integrated into ongoing activity that the user no longer maintains conscious awareness of it, acting through it rather than upon it."
用法说明 · 针对中文母语者
Dourish 把此概念挪用到 HCI，用以描述熟练、嵌入式的具身交互。中文译法不一（上手／应手／在手），Dourish 文本语境推荐「上手状态」。
常见错误
- ·字面误读为「方便可用」（handy）
- ·与 affordance 混淆：affordance 描述可被感知的行动可能，ready-to-hand 描述熟练使用后的退隐状态
真实用例 · 3 条
"this characterisation of everyday activity is rarely used in HCI but familiar to academic communities with wider reading habits as the 'readiness–to–hand' of Heidegger."
"A tool such as a hammer is ready–to–hand when, after using it for some time, one is familiar enough with its use to stop having to maintain conscious awareness of how one is using it while one uses it."
"With experience of its use, however, it may become understood and familiar, i.e. more ready–to–hand and embodied."