More than three years after its debut Windows 7 has finally overtaken Windows XP as the world's most widely used operating system, according to market research firm Net Applications. Market share for the decade-old XP steadily declined from 61.91% in September 2010 to 42.52% in August 2012. Windows 7 has gone from just 17.64% to 42.76% over the same period, barely overtaking XP by a fraction of a point.

Over the same two years, Windows Vista's market share has more than halved from 13.75% to 6.15%. Apple's combined share of the operating system market – counting versions 10.4 and after of OS X – is now at 7.13%, outpacing the ill-fated Vista for the first time, although individually the two most recent releases, OS X 10.8 Mountain Lion and OSX 10.7 Lion, hold a tiny 1.41% and 2.45% market share respectively.

All in all Microsoft controls 91.77% of the market, OS X 7.13%, and Linux sits at just 1.1%.

It's worth noting that StatCounter reported Windows 7 overtaking XP almost a year ago, and now puts Windows 7's market share at over the 50% mark. The discrepancy is explained by differences in the way each firm measures global traffic and process their numbers. Net Applications, for example, compares their traffic to the the CIA Internet Traffic by Country table and weighs their data accordingly to remove any bias by region.

When it comes to smartphone and tablet operating systems, Net Applications has Apple's iOS dominating the scene with a 65.94% market share, up from 61.5% in October 2011, while Google Android has grown from 18,86% to 20.93% in the same period. They are trailed from afar by Java ME (8.37%), BlackBerry (1.9%), Symbian (1.44%), Windows Phone (0.62%) and Windows Mobile (0.08%).