Launched on 30 March 2004, the site already attracts around 15,000 visitors every day.
Newsmap works by displaying Google news topics in visual form within a limited space. The user can quickly identify which news stories have been given the most coverage, viewing the map by region, topic or time.
"It's a relatively new way to look at news - you can see almost everything in a single screen," Mr Weskamp told dotJournalism.
Known as a 'treemap', this method of presenting information was invented in 1990 by Professor Ben Schneiderman, founder of the Human-Computer Interaction Laboratory at the University of Maryland.
Google News does an excellent job of aggregating a large amount of online news, said Mr Weskamp, but the aim of newsmap is to complement the service by helping web users measure the balance of news coverage on particular subjects.
"Compare news from New Zealand with the United States; the amount of news stories that the US carries is enormous," said Mr Weskamp.
"New Zealand newspapers don't really seem to carry much national news either.
"And if you jump to Italy, there is a small amount of international news, some national news and a considerable amount of sports stories."
Mr Weskamp plans to continue developing newsmap, and is working on new projects that involve visualising online social spaces and network traffic.
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