Gopher is a protocol - which is a part of the Internet protocol suite - that is used for retrieving documents on the Internet. Gopher is an alternative to the World Wide Web. Gopher was released in 1991; which was the same year that the World Wide Web was first available on the Internet. The Gopher protocol was initially outlined in Request for Comment's document: RFC 1436. Once the protocol was standardised, IANA (organisation who assign IP address blocks on the Internet) assigned TCP port 70 for the gopher protocol. Gopher was invented at the University of Minnesota by a team of computer scientists:
Gopher is viewed as having a rigid, efficient and strong hierarchical structure. This rigidity, while viewed as a strength, perhaps lacks the fluid "freedom" of the World Wide Web. Likewise, Gopher documents are required to adhere to a more stringent format in comparison to HTML documents (webpages). Gopher works on a client-server model - just like the World Wide Web - and until the release of the Mosaic web browser (client) in 1993 - which helped popularise the web - the Gopher protocol was a direct competitor to the World Wide Web.
The World Wide Web uses the HTTP (Hypertext Transfer Protocol) protocol to retrieve documents across the Internet. Gopher and HTTP are protocols that are included in the application layer of the Internet protocol suite. The first Gopher server was hosted by the University of Minnesota; this server could connect to Gopher server's worldwide. One of the strength's of gopher is the ease by which a gopher server can be setup. From 1991-1993, the use of Gopher expanded rapidly, with most universities in the US setting up their own server. However, a strategical error was made in 1993 - which probably led to downfall of Gopher as "the" dominant document retrieval system - when the University of Minnesota stated it would charge a fee for people to setup a gopher server. There has never been a fee charged to setup a web server.
As of 2014, Gopher is a protocol which is still being used to retrieve documents on the Internet. Veronica and Archie are two popular search engines that find Gopher servers and documents.