Hardware tweaking is a process of modifying certain parts of a hardware such as changing the cables, cleaning the heads of a VCR with a branded cleaning fluid or oiling the moving parts of an engine with the best possible oil.
Tweaks specifically designed to allow a processor to operate at a higher clock speed than normal are known as overclocking.
Modifications of computer systems not aimed at increasing performance, such as quieter fans, external controls, and decorations such as lights or windows, are known as modding.
There can be two ways of accomplishing this: manually (that is, if one is familiar with programming; though it may be irrelevant if the source of the application is closed, and there are no built-in means to adjust its performance) or using another piece of software specialized for that purpose.
Tweaking of this kind generally increases usability, in terms of personal configuration preferences, rather than objective performance of the system overall).