Various writing devices are designed to serve specialized purposes or “functions” to aid readers in their processing of a text. For example, an index lists important topics in the book and allows the readers to quickly locate the pages relevant to a particular topic. The purpose of this study was to learn what mature readers know about various functional devices. Two experiments were conducted to learn what readers know about functional devices in texts. Experiment 1 investigated readers’ knowledge about functional writing devices and Experiment 2 examined readers’ beliefs about the relevance of functional writing devices in various reading situations. At the end of the experiments, a list of functional writing devices and their respective usage was created from the results of Experiment 1 & 2. The information obtained could be useful for education purposes and also future studies on the effects of function identifying signals on cognition.