What does download mean?
Download is the transmission of data from the Internet to your device. The term "mbps" indicates, how many megabits per second were recalled. If an Internet connection with "up to 100 Mbps" is offered, this figure usually refers to the maximum download data rate possible. The terms and conditions of your Internet provider will often give a much lower minimum guaranteed data rate.
The data rate offered usually refers to the gross data rate, i.e. including additional data transmitted due to the network protocol used. The RTR-NetTest, however, measures the net data rate of a connection. This net data rate is about 10% lower than the gross data rate of your Internet connection.