Kensington Security Slot

Rightmost opening on the side of this laptop computer is a Kensington Security Slot

A Kensington Security Slot (also called a K-Slot or Kensington lock) is part of an anti-theft system designed in the early 1990s^[1] and patented by Kryptonite in 1999–2000,^[2] assigned to Schlage in 2002, and since 2005 owned and marketed by Kensington Computer Products Group, a division of ACCO Brands.^[3]