A master key system makes it possible for authorised people to gain access to different parts of a building with only one key. It eliminates the need to carry around a heavy key chain as it can open many different locks.
Access Control Systems are a popular alternative to more traditional type of access security. Landlords, business owners and owners of larger properties used to have to rely on the cutting and distribution of keys to various people who were to be granted access, which also required a level of trust to be built with each individual who receives one so placing the responsibility of keeping the building secure, in their hands. Access Control Systems reduce the risk and provide a more flexible option.