When you download RIMMF for the first time, you also download a set of demo records, just to give you something to practice with.
The records are:
tmq-demo-1 Fritz, Richard J. tmq-demo-2 Fritz, Deborah A. tmq-demo-3 Fritz, Deborah A. MARC21 for everyone tmq-demo-4 Fritz, Deborah A. MARC21 for everyone. Text tmq-demo-3 MARC21 for everyone. American Library Association. 2003. Volume
If you do not wish to keep these records in your data folder, you can choose the option to remove them.
You can also restore these records to your data folder, should you wish to do so, at any time.