Instant connection via computers and smartphones has become a fact of life for most people—what are the innovative ideas that power our modern information space?
Browsing online for anything—a person, a recipe, a fact or a date, a work of art, a concert ticket, a job—has become such second nature that it's hard to believe the web has only been accessible through a widely-used graphical web browser, Mosaic, since 1993.
And perhaps it's even harder to believe that something now firmly associated with fun and socialising, as much as with work and study, was created to make life easier for research scientists.
The information problem at CERN
CERN, the European Organisation for Particle Physics in Geneva, is a workplace like no other. It's home to 10,000 physicists and support staff, all engaged in experiments on the relationships between particles of matter that hold our world and everything in it together. Between them they generate vast amounts of data.
When the British physicist Tim Berners-Lee joined the CERN community in 1980, he immediately spotted that there was a problem.
The experimental data and supporting documentation were stored on a variety of computers in a variety of formats. It was almost impossible to track down everything that might be relevant to someone's research. A lot of information simply got lost.
Berners-Lee set out to solve that problem.
What was the idea behind the web?
At CERN, Berners-Lee immediately saw the need to link information across different sources, and created a hypertext system called ENQUIRE.
The inspiration for ENQUIRE was a quirky 19th century how-to book called Enquire Within upon Everything, which claimed to offer all the information you would need to understand the world or solve domestic problems.
Berners-Lee's system organised items of information into virtual 'cards', each of which could be linked to any other card.
What is hypertext?
In 1960, the American engineer Ted Nelson began to devise a project that he called Xanadu, which would extend the advantages of computing to all by storing documents in a linked fashion rather than hierarchically, and with no duplication.
He first coined the term 'hypertext' to describe the links in 1963, but his system was never fully implemented.
In the same decade at the Stanford Research Institute, the former radar technician Douglas Engelbart developed a system called oN Line System, or NLS.
NLS created a shared workspace where multiple users could edit documents that were cross-referenced through hyperlinks.
What were the key components of the World Wide Web?
When Berners-Lee returned to CERN full time in 1989, things had scarcely improved.
He proposed a system in which every source of information—what we now think of as a web page—would have a unique address, in a standard form, known as a uniform resource locator or URL.
Hypertext Transfer Protocol (HTTP) created a simple way of linking documents on the Internet, allowing you to navigate between one page and another. He also created a piece of software that presented documents in an easy-to-read format—the browser.
Already envisaging that his system could be extended way beyond CERN itself, he called the project WorldWideWeb.
The hardware behind virtual space
Berners-Lee has been quick to acknowledge that many of the ideas behind the World Wide Web did not originate with him, and some of the essential elements of the web were in place by the time he began working on it.
The 'hardware' of the system already existed in the form of computers linked over the Internet, using the TCP/IP protocol to ensure that they spoke a common language.
The idea of storing information with inbuilt links had been around since early in the 20th century, and built on by Ted Nelson and Douglas Engelbart's work on hyperlinks in the 1960s.
By 1990 Berners-Lee and his team were working with the NeXT computer, produced by a company founded by Steve Jobs. The computer had an advanced operating system, making it possible for them to rapidly develop software to demonstrate the features of the World Wide Web.
What is the impact of the web today?
The web became available for universal use on 30 April 1993, when CERN published a statement making the World Wide Web available on a royalty-free basis.
It has now become a truly democratic tool—anyone can add a server, own a domain name, create web pages or simply browse at will.
The rapid growth and spread of the web has been like opening Pandora's box—it's a powerful force for good, enabling voices to be heard and oppression to be exposed, but it has also created new spaces for fraud, theft, espionage and anonymous bullying.
The tension between policing the Internet community and retaining its global openness is one of the biggest challenges facing the world in the 21st century.