The Riddle

Emily is sitting at her desk playing a video game on her computer with a controller. The game instructs her to press "RT" to run. She stares at the monitor with a confused expression. Emily stops playing, bends over, and inspects the controller up close. This reveals the labeling of each of the controller's buttons. One of the buttons, the right trigger, is among them, which she stares at. Emily smiles and continues playing the game.

I guess I could memorize the controller button names, but… no.