In considering IT infrastructure, it should be noted that there is no such ideal as a standard computer installation. In some organisations, IT hardware may be located in a purpose built computer centre, where responsibility for its operation and maintenance is in the hands of specialist personnel, such as computer operators, systems programmers and operations analysts. In other organisations, IT hardware may also be located in a purpose built computer installation, but responsibility for its operation and maintenance may be vested in a smaller number of personnel who will perform a wider range of duties. In some organisations, IT hardware may be located in a user environment, where responsibility for such activities.