A keylogger silently operates on your computer, recording every keystroke you make and transmitting sensitive information such as passwords to a hacker.

Keystroke logging is the process of recording every keystroke made on a keyboard. You've probably heard about "keyloggers" while reading into malware – the tools used to carry out keystroke logging.

Kamkar says that his keystroke spying trick works best when he can aim his laser at a spot on a laptop that reflects light—ideally a shiny metal or plastic spot on the laptop's case, such as a logo.