A lockdown is a measure taken to restrict or limit movement and activities in order to prevent the spread of an infectious disease. It involves closing schools, businesses, public gatherings, and other places where people congregate, as well as implementing travel restrictions such as border closures or bans on mass transportation. The goal is to reduce human contact and limit opportunities for the virus to spread from person to person. Lockdowns are typically implemented during a pandemic or epidemic when health officials believe that the benefits of reducing transmission outweigh any negative consequences caused by restrictions on daily life.