Decent growth in sales of Linux and Mac operating systems helped the global OS market grow to $30.4bn last year.
The 7.8% year-on-year increase was a result of strong demand across all platforms with Microsoft holding its majority share of the market thanks to Windows 7.
"In the server OS market Linux was the fastest growing subsegment in 2010 as end ujsers adopted more open-standard systems," said Alan Dayley, managing vice president at Gartner.
"Within the OS market, IBM AIX had high single-digit growth, but Unix generally experienced modest or nrgative growth," he added.
In terms of vendor share Microsoft topped the chart with a 78.6% share followed by IBM and HP with 7.5% and 3.7%. Oracle managed to climb up from 8th to 4th position as a result of its acquisition of Sun's Solaris business.