"The web," or "world-wide web" is a term for the system of hypertext linked documents accessed over the internet, with a web browser. The
www that comes before most webpages is a reference to the "world-wide web."
In 1989, a British engineer, computer scientist and CERN employee (Tim Berners-Lee) wrote a proposal for what would become the web, publicly introducing the project in 1990 with Belgian computer scientist Robert Cailliau. The introduction of Mosaic (a graphical web browser) in 1993 by the National Center for Supercomputing Applications at the University of Illinois at Urbana-Champaign is widely regarded as the turning point for the web, which is now the most popular portion of the internet.
While the terms "web" and "internet" are often used interchangeably in colloquial language, they are not the same. The web is simply one of many services available on the inter-connected networks that make up the internet.