Bring Your Own Device, or BYOD, indicates the permission given by a company for their employees and/or visitors to use their own personal devices on corporate networks and sometimes to view privileged information. This is opposed to strictly allowing only business-owned devices.
BYOD often provides efficiencies, shows trust from the business and can even improve mental wellbeing in the workplace.
However, BYOD opens up the possibility of cyber attacks - increasing the attack surface of the organisation. In order to counteract this, good cyber security hygiene is advised from the business from a policy perspective, from a training perspective and from a technical perspective.