The first web browser
The first ever web browser was developed by Tim Berners-Lee and was called WorldWideWeb. It was completed in December, 1990 and introduced to a number of people at CERN in March, 1991. WorldWideWeb had a graphical user interface but it did not support graphics embedded in pages.
Other web browser soon followed:
But the first web browser credited with popularizing the World Wide Web was Mosaic, developed at the National Center for Supercomputing Applications (NCSA)at the University of Illinois Urbana-Champaign. After the initial beta versions, Mosaic v. 1.0 was released on November 11, 1993.
References and useful resources: