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Scratch input

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Scratch - Input and Variables

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Scratch Tutorial | How to do SPECIAL KEYS for INPUTS!

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User Inputs in Scratch - Keyboard

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User Inputs in Scratch - Ask Block

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3. Scratch Input, Variables and Output

In computing, scratch input is an acoustic-based method of Human-Computer Interaction (HCI) that takes advantage of the characteristic sound produced when a finger nail or other object is dragged over a surface, such as a table or wall. The technique is not limited to fingers; a stick or writing implements can also be used. The sound is often inaudible to the naked ear. However, specialized microphones can digitize the sounds for interactive purposes. Scratch input was invented by Mann et al. in 2007, though the term was first used by Chris Harrison et al.