Essentially, this involves asking real users to think aloud as they are performing a set of specified tasks using the product being tested. Users are asked to say whatever they are looking at, thinking, doing, and feeling, as they go about their task. This enables observers to see how users react to the product, and make changes accordingly. Observers at such a test are asked to objectively take notes of everything that users say, without attempting to interpret their actions and words. In fact, test sessions are often audio and video taped so that developers can go back and refer to what users did, and how they reacted to an interface.
The talk aloud method can also be used in the study of reading. Readers are asked to "think aloud" whilst reading to determine what inferences they are drawing from a text. In the development of reading tests, the method may be used to highlight areas of questioning.