Courier services are established to deliver messages, mails and packages to their desired destination. Courier services are quicker and efficient. Courier services are reliable. Courier services feature security, tracking, signature, specialization and individualization of express services, which makes them a class apart from ordinary mail service. Courier services use is restricted to packages and documents considered important enough to merit the cost. Courier services operate from within specific towns or cities, to regional, national and global services. Courier services in relation to consignments requiring delivery over greater distance networks often include lorries, aircraft and rail.