• The POP3 protocol derives at least some of its inspiration from the post office"ROYGBIV" is Copyrighted by Flickr user: SC Fiasco (Ed Siasoco) under the Creative Commons Attribution license.
  
  

History

• POP3 is the third version of the POP standard, with POP1 and POP2 being the originals. The POP3 standard for email delivery and retrieval was conceived in 1988 to circumvent the problems in maintaining access to email faced by those lacking a consistent Internet connection. Using POP3, one can download and send emails in small bursts, allowing for manipulation of the email messages while offline.
  
  Moreover, POP3 put users in control of their email messages. One of the central tenets of POP3 is the deletion of messages from the server once transferred to a local machine. This process ensures that the maintenance of a personal email database is purely the responsibility of the user.
  
  

Features

• POP3 access server-side messages from the Internet through standard TCP/IP connections. Because the protocol was originally designed to give users without an "always on" Internet connection easy access to their email, the number of commands available are limited. To put it bluntly, POP3 is a simple, yet ingenious email access and delivery application.
  
  

Function

• POP3 seemingly has an extremely small list of features, in spite of its popularity and widespread usage. Fundamentally, the only feature of POP3 is the manner and ease with which email messages are downloaded from the server to a local machine. This is accomplished quickly and efficiently through a process that is normally no more than three commands.
  
  In recent years, POP3 added a command to allow email messages retrieved from the server to remain undeleted, thus giving the user access online and offline.
  
  

Benefits

• The growth of "always on" broadband Internet connections have relegated one of the central benefits of POP3 to the backseat: that of fast and efficient access to server-side email. Even still, POP3 remains popular due to the ease of setting up a POP3 connection on a local machine. Accessing email through POP3 allows the user to backup all server-side emails if she wishes to keep messages undeleted, and gives those who primarily access through POP3 a consistent email experience.
  
  

Disadvantages

• POP3 lacks any online access to email. In other words, even if a constant Internet connection is maintained, messages are only ever viewable after they are downloaded from the server. POP3 also lacks commands to segment messages by server-side delivery rules. Any folders that messages are assigned to online will be ignored, thus making it necessary to organize client-side messages, as well. In general, POP3 lacks many valuable features offered by the Internet Message Access Protocol.