Internet Explorer, also known as IE, is a browser developed and owned by Microsoft. It was first released as part of the add-on package Plus! for Windows 95 that year. Later versions were available as free downloads, or in service packs, and included in the Original Equipment Manufacturer (OEM) service releases of Windows 95 and later versions of Windows.
Internet Explorer is one of the most widely used web browsers, attaining a peak of about 95% usage share during 2002 and 2003. This came after it managed to win the first browser war against Netscape, which was the dominant browser in the 1990s. Its usage share has since declined with the launch of Firefox (2004) and Google Chrome (2008), and with the growing popularity of operating systems such as OS X, Linux, iOS and Android that do not run Internet Explorer. Estimates for Internet Explorer's overall market share range from 16.9% to 57.38% (or even as low as 13.09% when counting all platforms), as of February 2015 (browser market share is notoriously difficult to calculate). Microsoft spent over US$100 million per year on Internet Explorer in the late 1990s, with over 1000 people working on it by 1999.