What device allows individuals to communicate by typing instead of speaking?

The correct answer is the TDD, which stands for Telecommunications Device for the Deaf. This device is specifically designed to facilitate communication for individuals who are deaf or hard of hearing by allowing them to send and receive text messages over a telephone line. Users type their messages on a keyboard, and the device transmits the text to another TDD device, where it can be read by the recipient.

The TDD is an important tool in telecommunication as it ensures that those who cannot use spoken language can still communicate effectively with others. It provides equal access to telephone communication, which is critical in emergency situations and everyday interactions.

Other devices mentioned may be related to communication technology, but they serve different functions. Understanding the specific capabilities of each device helps highlight the significance of the TDD as a vital means of communication for individuals with hearing impairments.