What is a Web Browser?
A web browser is an application that lets someone browse the World Wide Web. That’s sometimes called web surfing. That’s not as common a phrase as it used to be. Web surfing is usually used in terms of “not doing anything particularly important on the web”.
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NCSA’s Mosaic was one of the first commercial browsers. One of its most appealing features was its graphical interface and the ability to show inline graphics.
Mosaic is the celebrated graphical “browser” that allows users to travel through the world of electronic information using a point-and-click interface. Mosaic’s charming appearance encourages users to load their own documents onto the Net, including color photos, sound bites, video clips, and hypertext “links” to other documents. By following the links — click, and the linked document appears — you can travel through the online world along paths of whim and intuition.
The (Second Phase of the) Revolution Has Begun, Gary Wolfe, Wired Magazine, Oct 1994
The team that developed Mosaic formed their own company that developed Netscape Navigator. Microsoft licensed Mosaic from NCSA to create Internet Explorer.
Current modern browsers with significant market share are Google Chrome, Apple Safari, Microsoft Edge, Mozilla Firefox, and Opera. Chrome by itself has approximatly two-thirds of the market, so it’s highly recommended that you install and use that while developing, if you don’t already have it.