Web browser developed by Google.

Mac OS X is a line of computer operating systems developed, marketed, and sold by Apple Inc., and since 2002 has been included with all new Macintosh computer systems.

Mozilla Firefox is a free and open source web browser descended from the Mozilla Application Suite and managed by Mozilla Corporation.

Series of software operating systems and graphical user interfaces produced by Microsoft.

Windows 7 is the latest version of Microsoft Windows, a series of OSs by Microsoft for use on personal computers.

Safari is a web browser developed by Apple Inc. First released as a public beta on 7 January 2003, it became Apple's default browser beginning with Mac OS X v10.3 "Panther".

Windows XP is a line of operating systems produced by Microsoft for use on personal computers, including home and business desktops, laptops, and media centers.

Open-source computer operation system, Unix-like operation systems family. Used widely on servers, embeded devices and some smartphones. Originally written in 1991 by Linus Torvalds.

Windows Vista is a line of operating systems developed by Microsoft for use on personal computers, including home and business desktops, laptops, tablet PCs, and media center PCs.

Free open-source computer operating system based on the Linux. Sponsored by the UK-based company Canonical Ltd.