The American Century Short-Term Government Fund - R5 Class (TWUOX) is a mutual fund that primarily invests in short-term government securities, such as Treasury bills and notes. This fund is designed for investors seeking low-risk investments with a short-term investment horizon. The R5 Class designation indicates that this fund is available to institutional investors and has a lower expense ratio compared to other share classes. Overall, this fund offers a conservative investment option for those looking to preserve their capital while earning a modest return.