A theme, in computing, refers to a preset package of graphics and other elements that act as a way to customise an operating system or software application.  Most people are probably aware of the different Windows themes that are available across the different Microsoft operating systems, however, a number of individual applications also have different themes available to users.  The graphical themes for specific applications are often referred to as skins rather than themes, however the distinction between these two terms is often arbitrary.  Themes can provide users with a level of customisation and a feeling of individuality when using their computers.

Computer themes are so powerful because they allow users to change the appearance of a range of graphical and formatting elements at once, rather than having to change each element individually.  Specific themes for operating systems can often be loaded with a single click of a mouse, making them easy to change for even a novice computer user.  It is often possible to change certain individual elements within an operating system however, and dedicated desktop themes and application themes exist for this purpose.

Themes have become especially popular and accessible due to the development and popularity of the Windows operating systems.  A number of Windows XP and Windows Vista themes are available to users, with Luna and Royale being the most well known for Windows XP, and Aero being the most popular for Windows Vista.  Windows Aero is the default graphical user interface theme included in the Vista operating system, and includes a number of functional and aesthetic improvements over its predecessors.

Computer themes are an important element of software interfaces as they provide computer users with a level of customisation and control over their computing experience.  Many people spend a lot of their working and recreational time looking at a specific operating system, and simply changing the graphics and colour choices through a theme can have a big impact on the overall user experience.  As computer users become more educated and more used to alternate themes and skins on their computers, more complex customisation is likely to be the result, and themes are likely to play an even bigger part of operating system and application development.