section_path: Modern mail/Organization
section_name: Organization
paragraph_text: Organization
  
  Some countries have organized their mail services as public limited liability corporations without a legal monopoly.
  
  The worldwide postal system constituting the individual national postal systems of the world's self-governing states is coordinated by the Universal Postal Union, which among other things sets international postage rates, defines standards for postage stamps and operates the system of international reply coupons.
  
  In most countries a system of codes has been created (referred to as ZIP codes in the United States, postcodes in the United Kingdom and Australia, eircodes in Ireland and postal codes in most other countries) in order to facilitate the automation of operations. This also includes placing additional marks on the address portion of the letter or mailed object, called "bar coding". Bar coding of mail for delivery is usually expressed either by a series of vertical bars, usually called POSTNET coding or a block of dots as a two-dimensional barcode. The "block of dots" method allows for the encoding of proof of payment of postage, exact routing for delivery, and other features.
  
  The ordinary mail service was improved in the 20th century with the use of planes for a quicker delivery. The world's first scheduled airmail post service took place in the United Kingdom between the London suburbs of Hendon and Windsor, Berkshire, on 9 September 1911. Some methods of airmail proved ineffective, however, including the United States Postal Service's experiment with rocket mail.
  
  Receipt services were made available in order to grant the sender a confirmation of effective delivery.