tool use allows us to assess text entry in terms of its utility—how well it supports users in thatpursuit—and its usability—how easy it is to enter text and learn how to enter text.

For example, text entry methods such as eye typing are designed to allow nonspeaking users with motor disabilities to enter text using their eye movements only.

Tool use alsotriggers the concept of accessibility.

Thinking about text entry as

Text entry is also a good example of tool use (Chapter 19). A text entry method is a tool that allows the user to communicate with someone or something, typically other people or a service, using asynchronous text messages and longer documents.